The ongoing battle between hosts and pathogens has long been of interest to evolutionary biologists. N) often greatly exceed those of synonymous substitution per site , as expected if most mutations are fixed because they increase fitness  reported to date . In part fitness .At the host level, most studies of the selection pressures acting on immune system genes have concentrated on genes implicated in the adaptive immune response against microbial pathogens, particularly those producing antibodies , or geneN greater than dS in many comparisons , so that this nucleotide mutates to uracil (U). This is essential for various aspects of cellular function. APOBEC1, for example, is involved in the C→U editing of apolipoprotein B mRNA (therein christening the family), while another family member, the activation-induced deaminase, has a vital role in adaptive immunity in that it assists in the diversification of antibodies. Two more enzymes, APOBEC3G and APOBEC3F, form part of the innate immune system; they function as antiviral agents and are being intensively studied in the context of infection with the human immunodeficiency virus (HIV), the cause of AIDS. In particular, APOBEC3G targets the reverse transcription step of the HIV life cycle, in which the viral genomic RNA is converted into proviral DNA, which is then integrated into the host genome . APOBEC310 virions are produced in a single infected individual  that counters APOBEC3G . Hence, The intense selective pressure on the defensins and APOBEC3G illustrates that although the innate immune response is generalist in its action, it is as highly and intricately evolved as its better-studied ally, the adaptive immune system. Rather than being an evolutionary remnant, it is a dynamic and continually adapting system. Less clear is whether other host proteins act in the same manner as APOBEC3G. In particular, the most common and destructive pathogens faced by humans and other mammals are RNA viruses, such as influenza A, yellow fever, and hepatitis C. In most cases, our ability to survive these viral infections is simply a combination of good luck and good breeding; with the right combination of MHC alleles, itself a function of population history and what we by chance inherit from our parents, some individuals may be more able to fight off viral infections than others. The ubiquity of RNA viruses hints that our genomes might also contain an innate, yet highly adapted, defence system that targets this abundant class of pathogens by manipulating their mutation rate. Although utilizing lethal mutagenesis might one day be an important way to design new drugs against a variety of viral pathogens, it would come as no surprise if nature got there first.Adaptive immune system. The pathogen-specific part of the vertebrate immune system. It is comprised of two major arms, antibodies  and T-cells (the cellular response), both of which lay down an immunological memory for future defence.Innate immune system. The nonspecific part of the vertebrate immune system. It has a wide variety of components, ranging from lysozymes in saliva to cytokines, defensins, interferons, and natural killer cells in a variety of tissues.Endogenous retroviruses. The  dead remnants of functional retroviruses that are now passed on through the germ line like normal genes. It has been estimated that approximately 5% of the human genome is composed of endogenous retroviruses.


In February 2003, the first (and so far only) epidemic of severe acute respiratory syndrome (SARS) started in Guangdong Province, China. A respiratory illness that begins with a high temperature and can develop into life-threatening pneumonia, SARS is spread by close person-to-person contact. Before the end of the month, a Guangdong doctor had inadvertently taken the infection to Hong Kong. A woman staying in the same Hong Kong hotel as the doctor then carried the disease to Toronto. In March, the World Health Organization issued a global alert and warned against unnecessary travel to affected areas. Because of these and other containment efforts, 8,098 people became ill with SARS, rather than the predicted millions; 774 people died. The last case of the epidemic was reported in Taiwan in June 2003, and since then there have been only two cases in Singapore and nine in China.By May 2003, a coronavirus had been identified as the cause of SARS, and the full genome sequence of this new human pathogen, which may have jumped from civet cats to people, had been published. From the viral genome, researchers have deduced the sequences and structures of the viral proteins, hoping to use this information to develop treatments and vaccines for SARS. But could the structure of the RNA genome itself also be a target for antiviral drugs?The genome of the SARS virus is a single strand of RNA that folds into regular repeating patterns to form secondary structures such as helices. These then fold and bend in three dimensions to form complex tertiary structures. William Scott and colleagues have used X-ray crystallography to measure the exact positions of individual ribonucleotides and the interactions between them in a small segment of the SARS virus genome called the s2m element. This element sits at one end of the viral genome, and, as the researchers show, its sequence is highly conserved in related coronaviruses. Furthermore, unlike the rest of the SARS genome, which changes rapidly, the s2m element is absolutely conserved in SARS variants obtained from patients during the SARS epidemic. This strong sequence conservation indicates that the tertiary structure of s2m could be important for viral function, and when the researchers solved the three-dimensional crystal structure of the element, they found that it had a unique tertiary structure. In particular, there was a right-angle kink in its helical axis and a tunnel with a net negative charge.The biological role of a new protein can often be deduced by comparing its shape with that of proteins with known functions. Scott and colleagues used this approach to hypothesize that the function of the s2m element involves interaction with a conserved host factor during the SARS life cycle. Finding a similar 90° kink in a region of ribosomal RNA that binds factors necessary for the initiation of protein synthesis, the researchers speculate that the SARS virus may use the s2m element to hijack its host cell's protein synthesis machinery. This and other putative roles need to be tested experimentally, but given that the s2m element is absent in the human genome, its unusual structural features could be an attractive target for the design of antiviral therapeutic agents.


Neisseria meningitidis, as a consequence of the insertion of a restriction endonuclease-encoding gene, the 'dam replacing gene' (drg) at the dam locus. Here, we report the results of a survey to assess the prevalence of drg in a globally representative panel of disease-associated meningococci.DNA adenine methyltransferase (Dam) activity is absent in many, but not all, disease isolates of drg was absent in all representatives of the ST-8 and ST-11 clonal complexes tested, but uniformly present in the representatives of the other hyper-invasive lineages present in the isolate collection . The patterns of sequence diversity observed in drg were consistent with acquisition of this gene from a source organism with a different G+C content, at some time prior to the emergence of present-day meningococcal clonal complexes, followed by spread through the meningococcal population by horizontal genetic exchange. During this spread a number of alleles have arisen by mutation and intragenic recombination.Of the known meningococcal hyper-invasive lineages investigated, drg gene may contribute to the divergence observed among meningococcal clonal complexes, but does not have a direct mechanistic involvement in virulence.These findings are consistent with the idea that possession of the  Neisseria meningitidis, the causative agent of meningococcal meningitis and septicaemia, is a common inhabitant of the human nasopharynx, being asymptomatically carried by approximately 10% of the population [pulation . There ipulation -7 but, dpulation . These lpulation  and multpulation .DNA adenine methyltransferase (Dam) is an enzyme involved in the mismatch repair system of bacteria. During DNA replication, only the parental strand is fully methylated by the enzyme, since methylation is not immediate, allowing a mismatch on the newly synthesised strand to be excised and replaced . DisruptN. meningitidis has been contentious. Bucci et al., 1999 [siaD capsule gene, resulting in an increased virulence of some strains. In addition, the latter work suggested that all pathogenic isolates lacked Dam activity, the dam gene inactivated by the insertion of a putative restriction endonuclease, named 'dam replacing gene' (drg), with the genotypes dam+/drg- and dam-/drg+ being mutually exclusive. However, two subsequent studies [drg gene encodes a restriction enzyme, NmeBII that is similar to the Streptococcus pneumoniae DpnI restriction endonuclease which cleaves at GmeATC, but not at GATC, sequences [Dam methylation has been implicated in modifying the virulence of a number of bacterial pathogens -26, but l., 1999  suggeste studies ,29 have equences ,31.drg and its association with disease-associated isolates of N. meningitidis was examined by a survey of its distribution in a collection of isolates chosen to represent the known diversity of pathogenic meningococci [drg is present in some lineages but not others, this gene has spread in the meningococcal population by horizontal genetic exchange, possibly after the introduction of the drg gene from an exogenous source.In the present study the prevalence of ngococci . The resdam and the absence of drg, and vice-versa. Of the 84 isolates tested, 23 were indicated to be dam+/drg- and 61 to be dam-/drg+ by restriction analysis and PCR amplification  present in this collection. The ratio of non-synonymous to synonymous substitutions  was also similar to that seen in the MLST gene fragments. Three drg gene fragments  exhibited polymorphisms resulting in single base frameshifts, two resulting in stop codons  had an insertion corresponding to a 24-base direct repeat. The G+C content of drg at 42.4% was lower than that of the housekeeping genes, which were in the range 51.1–57.4%.The level of nucleotide diversity, as represented by number of alleles and polymorphic sites, along with the p-distances seen within ST Table , with a drg fragment sequences generated a star phylogeny with some net-like phylogenetic structure involving the drg-2 allele  of disease-associated isolates and 75% (11/15) of carrier isolates possessing the drg insertion. The isolate collection employed by the present investigation was chosen to be globally representative of meningococcal disease in the latter part of the 20th century, with multiple examples of each of the major hyper-invasive meningococci identified over this period. When analysed by clonal complex, which identifies hyper-invasive lineages, it was apparent that the drg insertion was absent from all of the isolates representing the ST-8 and ST-11 clonal complexes, both major hyper-invasive lineages but, conversely, drg was present in all representatives of the hyper invasive lineages represented by the ST-1, ST-4, ST-5, ST-41/44, and ST-32 complexes. This association was independent of the serogroup expressed by the isolates and provided a likely explanation of the earlier observations [dam locus. At a given point in time they may be dominated by drg containing meningococci, while at other times isolates without this insertion might dominate. For example, as both the ST-1 and ST 32 complexes contain the drg insertion, this insertion would be prevalent among the disease isolates recovered by the pandemic outbreaks caused by these clonal complexes [drg insertion. This observation highlights the importance of assembling genetically defined isolate collections with a prescribed sampling frame if comparisons of meningococci with potential for virulence are to be undertaken.The data presented here, however, do not support the contention that the rvations . As meniomplexes ,38; convomplexes ,40 woulddrg gene has been introduced into Neisseria from an exogenous source [drg gene compared to the meningococcal housekeeping genes was consistent with this idea; however, the levels of diversity among the drg alleles, which was similar to that observed in the meningococcal housekeeping genes, along with the reported occurrence of drg in other Neisseria species [dN/dS), which was also similar to that observed in meningococcal housekeeping genes, suggested that the drg gene had been subject to stabilising selection for conservation of function since its putative introduction into the meningococcal population, although the possession of frame shift mutations in some of the drg alleles demonstrated that, as with N. lactamica, not all meningococci possessing the drg insertion expressed the endonuclease [It has been suggested that the s source . The dif species , suggestnuclease . In othenuclease .Neisseria and may be related to the transformable nature of these organisms [drg in the dam locus, replacing a methylase with an endonuclease, may provide a potent barrier to genetic exchange from dam+ to drg+ meningococci; indeed, while there was evidence for the occasional horizontal genetic exchange of drg alleles among the genetically diverse meningococci that possess the insertion, there was no evidence for the transformational loss of drg from a given clonal complex among the isolates examined here. This concept of genetic isolation among lineages receives some support from the possession of porB2 alleles by members of the dam+ ST-8 and ST-11 complexes and porB3 alleles by the clonal complexes with the drg insertion [The presence of multiple methylation systems is a characteristic of the rganisms . Whole grganisms ,44. It irganisms  and in tnsertion ,39, but drg insertion may influence meningococcal population structure, the data presented here do not support a direct association of this genotype with meningococcal virulence.While it is possible that the possession of the Neisseria meningitidis [).The 84 isolates used in this study see  were a sngitidis . The colDpnI, DpnII, and Sau3AI, followed by separation of the digestion products by agarose gel electrophoresis. Each enzyme specifically recognises a cognate target site of GATC and cleaves this site depending on whether it is methylated or not: DpnI cleaves this target sequence only when N6-methyladenine is present within the recognition sequence; DpnII cleaves only unmethylated sites, and Sau3AI cleaves both methylated and unmethylated target sequences.The methylation status of the chromosomal DNA of each isolate was determined by restriction digestion with the restriction endonucleases dam gene was determined by polymerase chain reaction (PCR) performed using dam specific primers, DamF1 (5' – TAAAATGGGCAGGCGGCA – 3') and DamB2 (5' – CGTAAGGGGGATCGCAAT – 3'). These amplify a 534 bp fragment from the 5' end of the dam gene in dam+ strains but not from dam-strains. The presence of drg was determined by PCR using primers DrgF1 (5' – CATGAATTTATTTTTCGATA – 3') and DrgB2 (5' – AATTTGCAACTGTTGGCG – 3') that bind to drg internal sites and produce a 705 bp fragment in isolates containing the drg gene. PCR amplification was also performed using primer pairs Drg5F (5' – TGTCTAAAGAACTCAAAG – 3') / DrgB3 (5' – CGGTATCGAAAAATAAAT – 3') and Drg3F (5' – ATCCATCCAATTTCCCCA – 3') / DamB5 (5' – AAATGCCGTCTGAA – 3') based on dam and drg coding regions in order to confirm that dam inactivation was due to drg insertion.The presence of the drg gene were purified by precipitation with poylethylene glycol and sodium chloride as described previously [drg sequence was assigned an arbitrary allele number in order of discovery.Amplicons corresponding to the eviously  and theidrg gene fragments was performed using SPLITSTREE, version 3.1 [Percentage G+C was calculated using the program START . Split dsion 3.1 . The prosion 3.1  using thsion 3.1 .KAJ carried out the nucleotide sequencing and analysis of the data. LS performed the PCR screening of the isolates. ERM and MCJM conceived of the study and participated in its design and coordination.Bacterial isolates used in the studyClick here for file


The book "Understanding the Human Machine, A Primer for Bioengineering" embraces various aspects of biomedical engineering as an essential resource book for physical scientists, engineers and biomedical students. The book interfaces physiologic systems with engineering principles to capture the important concepts from a plethora of facts in field of biomedical sciences. Humors, exercise, history of biomedical discovery and elements of humility continuously emerge throughout the book; thereby, enhancing the self-taught approach for the new comers.The Introduction reflects the author's philosophy and advice for the readers from his accumulated wisdom and experience in teaching bioengineering. In Chapter 2, the author used the system approach to intertwine cardiovascular, renal, respiratory, gastrointestinal, endocrine, nervous and muscular systems. The organization is timely and effective in the era of systems biology and the emerging research towards predictive and preventive medicine.The system approach in Chapter 2 paves the way for detecting signal output from the physiologic systems. Biosensors are illustrated to measure electric signals from the visual, auditory and olfactory systems as well as the heart, brain, and muscle. The integration of electric circuits using the classic examples such as the Wheatstone bridge and operational amplifiers provides the frame work for signal acquisition and processing. Finally, the author completed the book with a touch of bioinformatics in the post genomic era.In general, the book is comprehensive and succinct, readable and interesting. The presented material spans from the fundamental principles to the applications of bioengineering.Certain areas will improve the quality of this book for the readership of undergraduates and new comers to bioengineering. Some figures are difficult to understand as a result of small captions (eg. figs 2.11 and 3.19). Others are old and lack clear labeling . Tissue engineering deserves a paragraph. Analogous to nanotechnology, a link to a tissue engineering website would be helpful for the readers. A paragraph on molecular engineering involving proteins, DNA and RNA molecules would enhance the balance between classic bioengineering and the emerging fields. The readers would be intrigued if the book ends with a paragraph introducing Bio-MEMS , bionanotechnology, molecular imaging, and surface chemistry.Overall, "Understanding the Human Machine, A Primer for Bioengineering" is a very useful book that highlights the fusion between organ systems and engineering principles. I would recommend this book as an introduction to bioengineering and a reference for students from physical science, engineering and life science.


Little is known about the prevalence of khat-induced psychotic disorders in East African countries, where the chewing of khat leaves is common. Its main psycho-active component cathinone produces effects similar to those of amphetamine. We aimed to explore the prevalence of psychotic disorders among the general population and the association between khat use and psychotic symptoms.In an epidemiological household assessment in the city of Hargeisa, North-West Somalia, trained local interviewers screened 4,854 randomly selected persons from among the general population for disability due to severe mental problems. The identified cases were interviewed based on a structured interview and compared to healthy matched controls. Psychotic symptoms were assessed using the items of the WHO Composite International Diagnostic Interview and quantified with the Positive and Negative Symptoms Scale. Statistical testing included Student's t-test and ANOVA.Local interviewers found that rates of severe disability due to mental disorders were 8.4% among males (above the age of 12) and differed according to war experiences . The clinical interview verified that in 83% of positive screening cases psychotic symptoms were the most prominent manifestations of psychiatric illness. On average, cases with psychotic symptoms had started to use khat earlier in life than matched controls and had been using khat 8.6 years before positive symptoms emerged. In most cases with psychotic symptoms, a pattern of binge use (> two 'bundles' per day) preceded the onset of psychotic symptoms, in contrast to controls of the same age. We found significant correlations between variables of khat consumption and clinical scales , and between the age of onset of khat chewing and symptom onset .per se but rather early onset and excessive khat chewing seemed to be related to psychotic symptoms. The khat problem must be addressed by means other than prohibition, given the widespread use and its role in Somali culture.Evidence indicates a relationship between the consumption of khat and the onset of psychotic symptoms among the male population, whereby not the khat intake  The leaves of the khat shrub alpha-aminopropiophenone) . Cathino disease ,25. The  disease  may also disease .The first goal of this study was to verify the impression of an unusually high prevalence of psychotic disorders in the city of Hargeisa via an epidemiological survey carried out in a representative sample of households. In addition, we wished to study the association between khat abuse and psychotic disorders. If khat abuse does induce psychotic disorders, a higher prevalence of psychotic diagnoses, mainly in men (as women rarely consume khat), was to be expected in Hargeisa compared to localities with less khat use. In addition, a case-control study served to examine whether individuals identified in the survey suffering from psychotic symptoms presented a pattern of khat consumption different from matched controls.In order to screen for households with mentally ill members, 612 households with 4,854 members were randomly selected as representative of the city of Hargeisa . For household selection the town was first subdivided into 30 sections of approximately equal populations. For this purpose we used the same sections as UNICEF in their assessment of vaccination coverage for children in October 2002, which were defined in a joint approach by UNICEF and the municipality of Hargeisa. A section had to be subdivided into square-shaped clusters if it was L-shaped, had a natural boundary within its limits (e.g. a steep hill) or had a much greater length than depth. A map for each section or cluster was produced using an aerial photograph. For random selection the geographical center of each cluster was determined and a random direction was chosen using a compass, a watch and a list of random numbers between 1 and 12 . Following the random direction until the border of the cluster was reached, all houses on the right side within a range of 15 meters were numbered. The first household to be approached was selected by a second set of random numbers. The next houses were selected by door-to-door distance until the predefined number was reached. Trained local staff interviewed the heads of the 612 households. If the head of household was not available, another adult member of the household was asked to answer to the questions. If no household member could be interviewed, the next house was selected according to the selection procedure.The following question was used to determine whether a person severely disabled due to mental health problems resided in the household: "Are there any members of your household who currently have mental problems that are so severe that the person has been unable to provide income or has been unable to help in the household for at least four weeks?" This criterion was fulfilled for 169  cases. These individuals will be referred to as 'positive screening cases'. A subsample of 52 'positive screening cases' was then randomly selected and examined in a clinical interview. In this group there were 44 males and 8 females. These individuals will be referred to as 'examined cases'.For each 'examined case' a matched control, who did not meet the criteria for disability due to mental health problems, was identified. Controls were matched by gender, age, and educational level. These 'case controls' were subjected to the same clinical interview as the examined cases. Forty-nine of the 52 examined cases and one control were diagnosed with psychiatric or neurological disorders (on this basis we estimated a sensitivity of 0.98 and a specificity of 0.94 for the screening procedure). We included only those forty-three examined cases (82.7%) in the further analysis who – in addition to the impairment of function – showed as main manifestations of mental problems at least one very severe or two moderate positive psychotic symptoms in the absence of organic somatic damages that might explain them; from hereon these are termed 'cases with psychotic symptoms'. The disorders of other examined cases were stroke (2), traumatic brain injury 1), mental retardation (2), and dementia (1). The case control with a positive diagnosis reported hallucinations with intact reality testing during khat intoxication and was replaced by a healthy individual. Socio-demographic characteristics for the two studied groups are summarized in Tables , mental All interviews were carried out in October and November 2002. Prior to the interview, participants were informed about the background of the study and the survey procedure. All participants signed a written informed consent, which was first read and explained to them (as most of the participants were illiterate). In the case of mentally challenged participants, background and procedure were also explained to the responsible caretakers whose written informed consent was a prerequisite for their participation. Interviews were approved by the local authorities and the National Demobilization Committee of Somaliland. Representatives of the different communities were informed and invited to observe the assessment in the field. Newspaper advertisements, daily radio programs and flyers informed the population about and helped them to understand the real purpose of the assessment . Consequently, the level of cooperation was extremely high. Out of 73 households approached under the supervision of the first author only three refused their participation. Therefore, we estimate that in total less than 5% of all households refused participation.Local interviewers were recruited among NGO and hospital staff who already had experience in working with mentally disabled persons. They participated in a two-week training course, which involved teaching the basic psychiatric concepts (e.g. psychotic symptoms), interviewing skills, training on the screening-instrument and field work under close supervision of experts. After the end of the course, fourteen of the seventeen trainees were employed for the duration of the study. Five interviewer teams, each comprising one male and one female interviewer, and four local supervisors did the field work. The local supervisors received additional training on the random sampling method. During the first weeks of interviewing the first author closely supervised the teams in the field.The screening interview assessed individual socio-demographic information, khat consumption and experiences in the civil war . Khat consumption (number of bundles/week) was assessed for the week prior to the interview. The household economic situation was approximated as the sum of four significant assets  and type of housing Table .Clinical interviews were carried out by some of the authors , all trained in the assessment of psychotic disorders and PANSS rating. Socio-demographic information and war-history were detailed. A standard event list was used to quantify the number of traumatic event types a person had experienced; the list included 11 types of events: active combat experience, accident, natural disaster, witness murder or killing, rape, sexual molestation, physical assault, being kidnapped or captured, torture, other, or suffered shock because a close person had experienced a traumatic event. In a short semi-structured qualitative interview the main areas of psychological condition and functioning were assessed. Additionally, psychotic symptoms were assessed using the items of the Composite International Diagnostic Interview (CIDI), Section G . The indClinical interviews were administered in the English language with the help of trained local interpreters, who had participated in the same training course as the interviewers. After the interview, the interviewing psychologist rated the current psychopathology using the Positive and Negative Syndrome Scale, PANSS .All items of the standardized interviews were translated from English into Af Somali by mixed teams of clinical experts and bilingual staff. Several steps of independent back-translations and corrections were necessary until a satisfactory translation was achieved. Content validity was assured by the involvement of clinical experts at all levels of the translation process. Also, interpreters were introduced to the concepts targeted by the respective questions.2-tests (or Fisher's exact tests), binomial testing, Student's t-test or Wilcoxon, and ANOVA or Krsucal-Wallis test . Univariate Analysis of Variance (ANOVA) was used to explore the effects of war-trauma on the khat intake. Means and standard deviations are reported.Differences between cases and controls were confirmed using chiOf the sample of 4,584 inhabitants of Hargeisa the screening interview disclosed 169 positive screening cases (i.e. 3.5%). Positive screening cases were more often male than female  than in male civilian war survivors of the same age  of the examined cases. Retrospective investigation suggested that the onset of psychotic signs occurred at the age of 23.4 ± 9.9 years .PANSS ratings of these 43 cases showed a substantially higher magnitude of current psychotic symptoms compared to a sample of 240 medicated schizophrenic patients  in the fFifteen of the 43 cases with psychotic symptoms (35%) were under current medication at the time of assessment; another nine (21%) had received medication in the past. A variety of drugs had been given, ranging from neuroleptics (12 patients) to prometazine (6), benzodiazepines (3), tricyclic antidepressants (3), carbamazepine (1) and other unknown drugs (10).Uncontrollable  behavior had led to restraint of cases with psychotic symptoms by chaining them to an object in 28 of the 38 men (i.e. 74%) and 3 of the 5 women (i.e. 60%) (p = 0.608). Additionally, 9 men (24%) and 3 women (60%) had been locked up to control their behavior (p = 0.589). On average, the 31 cases with psychotic symptoms who had ever been chained had spent 4.2 ± 5.2 years in chains  and the 10 cases who had ever been locked up spent on average additional 5.2 ± 6.5 years restrained .The proportion of khat user was higher among cases with psychotic symptoms than among matched controls: all except one of the 38 male psychotic cases, in contrast to 25 of the 38 male controls, had used khat (p < 0.001). In the cases with psychotic symptoms, regular khat consumption had started at an earlier age (16.6 ± 4.8 years) than among their matched controls , General Psychopathology , Anergia  and Thought Disorder , while the amount of khat consumed prior to onset of psychotic symptoms correlated significantly with the subscale Paranoia/Belligerence  and the Supplemental scale . The amount of khat consumed in the week before the interview correlated with the PANSS subscale Anergia .2 = 0.620). In Figure The number of traumatic event types experienced did not differ between cases with psychotic symptoms and matched controls . Also, the age when the first traumatic event was experienced did not differ between them . In order to estimate the relationship between number of experienced traumatic events and khat intake we used univariate ANOVA with khat intake before onset of psychotic symptoms (for controls at the age of symptom onset of matched pair) as dependent variable, and number of traumatic events in three categories  and being a case or a control as independent variable. We found significant effects for the number of traumatic events  and for the variable 'case or control'  and a significant effect of their interaction   In a representative subsample of male inhabitants of Hargeisa (older than 12 years) we found 8.4% severely disabled due to mental problems; of these, 83% had severe psychotic symptoms. Compared to the prevalence rates of psychotic disorders reported for male samples elsewhere ,32 this (2) Khat abuse showed a significantly earlier onset and was more frequently excessive in male cases displaying psychotic symptoms than in matched controls.(3) There is a higher vulnerability to disability due to mental disorders in those groups of society who were directly involved in combat in the past.(4) Among the positive screening cases examined and their matched controls we found that khat intake before the onset of psychotic symptoms (respectively at the same age for matched controls) was higher when more traumatic events had previously been experienced.These results are intriguing, as we may have detected only the very tip of the iceberg with our sub-optimal screening procedure, leaving less severe cases of mental and neurological disorders undiscovered.per se but rather specific patterns of it that are related to psychosis, especially early onset in life and the excessive intake (> two bundles per day). Both seem to be related to active participation in war, e.g. child ex-combatants used khat while fighting in order to counteract fear and enhance performance [The findings of the present study suggest that there is an association between khat consumption and psychosis; however the existence of a causative relationship and its direction between the two remains unclear. Furthermore, it seems that it is not the consumption of khat formance . Excessiformance . Our datKhat consumption might be related to the outbreak of psychosis in various ways. Considering psychoses as the result of genetic and acquired vulnerability and additional stress factors, the early onset of khat abuse may have substantially increased the risk in already vulnerable individuals. In animal studies, damage imposed on the developing brain, e.g. by drugs, increases the potential of amphetamine-like agents to change neuro-chemical systems and to induce psychotic-like behavior . In humaMoreover, khat consumption may affect the course of a psychotic disorder and the maintenance of symptoms. In contrast to the high khat consumption prior to the onset of psychotic symptoms, the amount of current khat consumption did not differ between cases with psychotic symptoms and controls and a significant number of patients did not have current access to the drug. Drug-effects on the course of illness may be attributed to sensitization  or to laSome methodological shortcomings of the study are related to the nature of field work in this specific post-conflict setting, which involved restricted freedom of movement due to the security situation and limited resources. However, although a perfect design is not possible in a rather complex field situation, the importance of such studies is evident from the fact that little or no information from post-war Somalia is available. First, we could not control whether our sample was comparable to the population from which it was drawn due to the lack of recent statistics in Somalia.Second, the validity of our screening and clinical interview can be questioned because of various points, e.g. whether the descriptions of symptoms and disability might be adequate for the Somali culture, or whether factors such as interpretation or the interviewing of a whole family rather than a single patient might distort the information. In our approach we decided to use disability as a selection criterion and a descriptive rather than a normative approach to identify the reasons for it. Thus, we decided to use the more unspecific terms 'cases with psychotic symptoms' or 'psychotic symptoms' rather than 'schizophrenia' or 'drug-induced psychosis'. However, the fact that our local interviewers found 123 of the 169 positive screening cases (72.8%) restrained, i.e. chained or locked up, and the overall high average PANSS scores of the examined cases, show that there are 'hard' criteria, which justify the use of the term 'psychosis' and validate our screening. Nevertheless, we recognize that with our method we must have failed to discover persons suffering from psychotic and other mental disorders . But assuming that this error is somehow the same for the whole sample, our finding that the group of society that engages most in khat chewing  most often suffers severe impairment due to mental disorders shows evidence that khat is related to mental health problems.Thirdly, the fact that we could not choose our matched controls from the pool of negative screening cases – the resources that would have been necessary to (repeatedly) contact and arrange appointments with them exceeded our capacities – leads without any doubt to an overestimation of the specifity of our detection procedure.Furthermore, the retrospective third-person assessment of the onset of psychotic signs, as well as the retrospective and subjective assessment of khat use, will have introduced some error variance in the data. However, we believe that especially in the Somali culture khat intake cannot be compared to any food intake, of which the retrospective assessment is problematic. In the Somali culture khat has a special significance, which also comes from existing traditional knowledge about its dangers. Therefore we suppose that retrospective assessment of khat intake is more valid than that of food intake. Also, the effects of social desirability might have affected both the detection of positive screening cases and the assessment of khat use. The fact that dozens of families approached the compound of our collaborating partner agencies in order to find help for their mentally ill members (often they brought them in chains to the compound) shows the great need for mental health services. Thus, the tendency to hide family members from our interviewer teams can be estimated as marginal. On the contrary, during the interviews our greater fear was that households would over-report the presence of mentally challenged family members. For this reason, we counted only those persons as positive screening cases when their existence in the household could be validated . The assessment of khat consumption is another point where effects of social desirability can be assumed. Whereas the information given by examined cases could be validated by the information of family members, we were well aware of the danger that the matched controls might have under-reported their khat intake. In order to allow for this in the interview we spent much time and effort to identify the real khat intake . Nevertheless, the high correlations validate the assessment procedures.Also, the sample size was too small to answer some of the questions in detail, especially the small number of female examined cases. However, the results were nonetheless statistically very robust.In sum, our design could not determine the existence of a causal relationship between khat and psychosis – this would have been too ambitious a goal. However, our main findings do not contradict the hypothesis that khat might cause psychosis.Future research should focus on the question of causality. Unfortunately, the Horn of Africa is probably the region where stimulant abuse currently reaches highest levels on a world-wide scale. This circumstance offers a unique research opportunity for cross-sectional and repeated measurement studies, which would enable us better to understand the relationship between schizophrenia and drug effects and to fill the gap in knowledge related to khat use. At the same time, the alarmingly high prevalence of khat chewing among persons who suffer from psychotic symptoms in one of the countries of its highest use, and the magnitude of human suffering associated with it, demands the development of adequate community-based prevention and treatment interventions. The usefulness of standard procedures derived from developed countries and brought to the Horn of Africa must be viewed in a "service-research attitude". We beliNot khat intake per se but rather specific patterns of it are linked to the development of psychotic symptoms, like early onset in life, excessive chewing (> 2 bundles/day) and use as self-medication for war trauma related symptoms. Although we cannot establish a causal relationship between khat and psychosis, we find some evidence that the prevalence of psychotic disorders is increased among the male adult population of Hargeisa. Ex-combatants are the group in society who are most affected by severe mental disorders, among them we find the highest abuse of khat. The way of khat use in Hargeisa is changing, indicated by e.g. the development of a group of heavy users who show consumption patterns similar to amphetamine addicts in Western countries. Measures of prevention and treatment of and further research on khat-related severe mental disorders have to be undertaken, however, taking into consideration that khat is an integral part of the Somali culture, which cannot simply be prohibited.The author(s) declare that they have no competing interests.Development of the study design and selection of instruments were accomplished by MO, FN, TE, MS, BR and HeH. MS, TE and MO performed pilot studies. Training and supervision of local interviewers was provided by MO, HaH, FN and BL. Clinical interviews were conducted by MO, MS, CC and BL. Statistical analysis was performed by MO and TE. The article was composed and revised by MO, TE, BR, FN and HeH.The pre-publication history for this paper can be accessed here:


Tumor microenvironment, which is largely affected by inflammatory cells, is a crucial participant in the neoplastic process through promotion of cell proliferation, survival and migration. We measured the effects of polymorphonuclear neutrophil (PMN) conditioned medium alone, and supplemented with serine proteinase inhibitor α-1 antitrypsin (AAT) or its C-terminal fragment (C-36 peptide), on cultured lung cancer cells.3H]-thymidine incorporation, Matrigel invasion and ELISA methods, respectively.Lung cancer HCC cells were grown in a regular medium or in a PMN-conditioned medium in the presence or absence of AAT (0.5 mg/ml) or its C-36 peptide (0.06 mg/ml) for 24 h. Cell proliferation, invasiveness and release of IL-8 and VEGF were analyzed by [Cells exposed to PMN-conditioned medium show decreased proliferation and IL-8 release by 3.9-fold, p < 0.001 and 1.3-fold, p < 0.05, respectively, and increased invasiveness by 2-fold (p < 0.001) compared to non-treated controls. In the presence of AAT, PMN-conditioned medium loses its effects on cell proliferation, invasiveness and IL-8 release, whereas VEGF is up-regulated by 3.7-fold (p < 0.001) compared to controls. Similarly, C-36 peptide abolishes the effects of PMN-conditioned medium on cell invasiveness, but does not alter its effects on cell proliferation, IL-8 and VEGF release. Direct HCC cell exposure to AAT enhances VEGF, but inhibits IL-8 release by 1.7-fold (p < 0.001) and 1.4-fold (p < 0.01) respectively, and reduces proliferation 2.5-fold (p < 0.01). In contrast, C-36 peptide alone did not affect these parameters, but inhibited cell invasiveness by 51.4% (p < 0.001), when compared with non-treated controls.Our data provide evidence that neutrophil derived factors decrease lung cancer HCC cell proliferation and IL-8 release, but increase cell invasiveness. These effects were found to be modulated by exogenously present serine proteinase inhibitor, AAT, and its C-terminal fragment, which points to a complexity of the relationships between tumor cell biological activities and local microenvironment. The relationship between inflammation, innate immunity and cancer is widely accepted. Early in the neoplastic process, inflammatory cells and their released molecular species influence the growth, migration and differentiation of all cell types in the tumor microenvironment, whereas later in the tumorigenic process neoplastic cells also divert inflammatory mechanisms, such as metalloproteinase production, and chemokine/cytokine functions to favour tumor spread and metastasis -3. Humanin vitro -thymidine incorporation assay  compared to control cells cultured in a regular medium. Thus, our data show that both PMN-conditioned medium and AAT loose their inhibitory effects on cancer cell proliferation when used in combination. Under the same experimental conditions, the C-36 peptide of AAT added either directly to HCC cells or as a supplement with PMN-conditioned medium did not exert any significant effects on HCC cell proliferation relative to controls  or its C-36 peptide (0.06 mg/ml) on lung cancer HCC cell proliferation, we measured DNA biosynthesis using a  Thymidine was then added (0.2 μCi/ml) for a further 4 h at 37°C. The medium was then aspirated, the cells were washed twice with 0.5 M NaCl and incubated for 5 min with 5% trichloroacetic acid. The cells were then washed with distilled water, dissolved in 1 ml 0.5 M NaOH, neutralised with 200 μl HCl and radioactivity determined in a β-counter . Protein concentration in cell lysates was determined by the Lowry method using HSA as a standard.HCC cells were incubated with test substances for 20 h. [6 cells/ml alone or together with test substances. Each suspension was added to the upper chamber of an ECM Invasion system. Medium containing 10% of fetal bovine serum (FBS), serving as a chemoattractant, was added to the lower chamber. The chambers were incubated at 37°C in 5% CO2 for 24 h. Invasive cells were stained and counted using microscope  at a 100 × magnification. The number of cells per field, from 10 randomly selected fields, are presented.Cell invasion assay was performed in an invasion chamber, a 24-well tissue culture plate with 12 inserts. The inserts contain an 8 μm pore size polycarbonate filters over which is placed a thin layer of ECMatrix™. HCC cells were suspended in a serum free medium containing 1 × 10HCC cells were cultured alone or stimulated with test substances for 24 h. Cell free supernatants were then analysed by zymography using 10% and 12% Tris-Glycine gels containing 0.1% gelatin or β-casein, respectively . Briefly, supernatants were diluted in a sample buffer and separated by electrophoresis at 125 V for 90 min. The gels were then renatured and developed over night in a developing buffer  at 37°C. After washing, the gels were stained with Coomassie Blue R-250. Proteases that can utilize casein or gelatine as a substrate showed up as clear zones in the gels.HCC cell supernatants were analysed for the VEGF and IL-8 levels by using commercially available quantitative ELISA kits  according to manufacturers instructions. The lowest detectable concentration for VEGF and IL-8 was 15.6 pg/ml and 10 pg/ml, respectively.HCC cells supernatants were analysed by 10% SDS-PAGE gels and when transferred to a polivinylidene fluoride (PVDF) membrane  using a semi-dry immunoblot transfer system. The blot was visualised using polyclonal rabbit antibody to human AAT (1:500) , secondary horseradish peroxidase-conjugated swine anti-rabbit antibody (1:800)  and peroxidase substrate, DAB  .The differences in the means of experimental results were analysed for their statistical significance with the one-way ANOVA combined with a multiple-comparisons procedure (Scheffe multiple range test), with an overall significance level of α = 0.05. Statistical Package  was used for the statistical calculations.AAT – alpha1-antitrypsin; C-36 – C-terminal fragment of AAT; FBS – fetal bovine serum; NSCLC – non small-cell lung cancer; MMPs – matrix metalloproteinases; MT-MMP – membrane type matrix metalloproteinase; PBS – phosphate buffered saline; PMN – polymorphonuclear neutrophil; VEGF – vascular endothelial growth factor.Inga Zelvyte – AB, Tim Stevens – JY, Ulla Westin – JY, Sabina Janciauskiene ES, FG


Adult T-cell leukemia (ATL) was first reported as a distinct clinical entity in 1977 in Japan. The predominant physical findings are skin lesions, lymphadenopathy and hepatosplenomegaly. The ATL cells are of mature T-helper phenotype and have a characteristic appearance with indented nuclei. There is striking frequent hypercalcemia with increased numbers of osteoclasts. Central to the identification of the disease is a striking geographic clustering in southwestern Japan and the isolation of human T-cell lymphotropic virus type-1 (HTLV-1) from the cell lines of patients. Worldwide epidemiological studies have been made through international collaborations. Several diseases were found to be related to HTLV-1 infection. Moreover, it was noted that an immunodeficiency state may be induced by HTLV-1 infection. In Japan, HTLV-1 carriers have been estimated to be 1.2 million, and more than 700 cases of ATL have been diagnosed each year. Adult T-cell leukemia (ATL) was described as a distinct clinical entity in 1977 in Kyoto, Japan . The illIt was around the 1973 that we came to recognize the existence of ATL, previously an unknown disease. I would like to give a retrospective view concerning the background of our studies on ATL.Many clinicians in Japan probably feel that the descriptions of diseases in the literature from abroad differ from the features of the diseases observed in their practices in Japan. We can mention many examples in the field of hematology. One of these is that the incidence of chronic lymphocytic leukemia is quite low, being only 2% of all hematological malignancies. What differs is not only the incidence but also the detailed symptoms and signs of diseases. This vague feeling that an autochthonous pathology exists in Japan may be considered as key factor in the background of our study of ATL.The second major factor is the recent progress made in basic immunology. Having an interest in immunoglobulin abnormalities, I studied multiple myeloma and related diseases in the days when even the word 'immunoglobulin' was not yet in use. The central theme of immunology at that time was to identify the structure of antibodies. Immunology has advanced rapidly, and myeloma was defined as a B-cell malignancy. Therefore, it was quite natural to enlarge the objectives of our clinical studies to all lymphoproliferative diseases.At this stage of our research in Kyoto, joint studies with young researchers were initiated. This was the third and most important element of the background of our ATL study. I became acquainted with Drs. Takashi Uchiyama and Junji Yodoi, who are currently both working in Kyoto, during their postgraduate training. Dr. Yodoi prepared an antiserum against human thymocytes and invited us to direct our attention to T-cells.In the course of examining patients with various lymphoproliferative disorders, we arrived at the conclusion that ATL was a disease which had not been described anywhere before. It was recognized that T-cell malignancy had a relatively high incidence among Japanese adults and that most of the patients with this disease were from Kyushu. This discovery was made from our bedside observations rather than from laboratory work. Thereafter, Dr. Uchiyama went to the National Cancer Institute, Bethesda to work with Dr. Thomas A. Waldmann and raised a monoclonal antibody, called 'Tac' antibody, which later played an important role in our ATL studies. Dr. Yodoi has developed a new field of research by identifying a novel cytokine, ATL-derived factor (ADF), which has proved to be important in redox regulation. At the end of 1981, I moved from Kyoto to Kumamoto, which is located in the middle of Kyushu. Our studies advanced remarkably there, due mainly to the efforts of excellent young co-workers including Drs. Kazunari Yamaguchi, Toshio Hattori, and Masao Matsuoka, who are now independently working in Tokyo, Sendai and Kyoto, respectively.th International Congress of Hematology in Kyoto, it was stated that 'attempt to elucidate leukemogenesis in this disease should be directed towards exploring the genetic background and a possible viral involvement'. HTLV (human T-cell leukemia virus), the pathogen of ATL, was first reported by Dr. Robert C. Gallo and his co-workers in Bethesda in 1980 and 1981. They isolated HTLV from cultured cells taken from a patient with an aggressive variant of mycosis fungoides and another with Sezary syndrome. Although both patients were said to have cutaneous T-cell lymphoma, they had some unusual features which, in retrospect, linked them to the clinical entity now called ATL.This discovery of ATL ushered in some dramatic developments in oncology, virology and, unexpectedly, neurology and other fields of medicine. When we reported a series of 13 patients with ATL in 1976 on the occasion of the 16In Japan, co-culturing of ATL cells with umbilical cord lymphocytes was first done successfully by Dr. Isao Miyoshi's group in Okayama, who obtained the cell line MT-1. Dr. Yorio Hinuma and his co-workers in Kyoto demonstrated that ATL patients have antibodies against presumed viral antigens on MT-1 cells by indirect immunofluorescence method. Subsequently, a retrovirus was isolated and called ATLV (adult T-cell leukemia virus). Since Dr. Mitsuaki Yoshida and his group in Tokyo showed that HTLV and ATLV are, in fact, identical, the term HTLV-1 (human T-cell lymphotropic virus type 1) has been commonly used.Furthermore, the following observations have been successively reported to support the etiologic association of HTLV-1.1. All patients with ATL have antibodies against HTLV-1.2. The areas of high incidence of ATL patients correspond closely with those of high incidence of HTLV-1 carriers.in vitro.3. HTLV-1 immortalizes human T cells 4. Monoclonal integration of HTLV-1 proviral DNA was demonstrated in ATL cells.Thus, HTLV-1 is the first retrovirus directly associated with human malignancy.The diagnostic criteria for HTLV-1 associated ATL have been defined as follows:1. Presence of morphologically proven lymphoid malignancy with T-cell surface antigens .2. Presence of antibodies to HTLV-1 in the sera.3. Demonstration of monoclonal integration of HTLV-1 provirus by Southern blot method.Virological study led us to classify the patients with ATL into four clinical subtypes according to the clinical features: acute, chronic, smoldering, and lymphoma. The acute type is the prototypic ATL in which patients exhibit increased number of ATL cells, frequent skin lesions, systemic lymphadenopathy, and hepatosplenomegaly. Most of these patients are resistant to chemotherapy and have a poor prognosis. In chronic ATL, white blood cell count is mildly increased, and skin lesions, lymphadenopathy, and hepatosplenomegaly are sometimes exhibited. In the past, chronic ATL was thought to be 'chronic T-lymphocytic leukemia'. Smoldering ATL is characterized by the presence of a few ATL cells in the peripheral blood over a period of years. Frequent symptoms are skin or pulmonary lesions. Chronic and smoldering ATL often progress to acute ATL after a long period (crisis). Lymphoma-type ATL is characterized by prominent systemic lymphadenopathy, with few abnormal cells in the peripheral blood. This type has been diagnosed as nonleukemic malignant lymphoma. Later, the Lymphoma Study Group in Japan proposed a practical diagnostic criteria for classifying ATL into these four subtypes.HTLV-1 is endemic in southwestern Japan, especially Kyushu and Okinawa, in the Caribbean Islands, and in Central Africa. It has been revealed that there are HTLV-1 carriers in South America, Papua New Guinea, the Solomon Islands, South China, and other isolated populations in the world, including Ainus in Hokkaido and Aborigines in Australia. These epidemiological studies have been promoted by international collaborations, to which Drs. William A. Blattner in Bethesda, Guy de The in Paris, Kazuo Tajima in Nagoya, Shunro Sonoda in Kagoshima, and many other epidemiologists have made important contributions. Dr. Daniel Catovsky and his colleagues in London delineated the clinical features of ATL patients originating in the Caribbean islands.On the other hand, several diseases have been found to be related to HTLV-1 infection. Drs. Antoinne Gessain and Guy de The first reported the association of tropical spastic paraparesis (TSP) and HTLV-1, and Dr. Mitsuhiro Osame and his co-workers in Kagoshima studied features of HTLV-1-associated myelopathy (HAM/TSP) in detail. HTLV-1 uveitis was subsequently described by a study group of ophthalmologists in Kyushu. HTLV-1 may also be associated with bronchopneumonitis, arthritis, polymyositis and other inflammatory conditions. Moreover, it was noted that an immunodeficiency state may be induced by HTLV-1 infection.In Japan, HTLV-1 carriers have been estimated to be 1.2 million, and more than 700 cases of ATL have been diagnosed each year. Majority of HTLV-1 transmission occurs via one of three routes, all of which require the passage of virus-infected cells. HTLV-1 carrier mothers transmit the virus to newborns mainly through breast milk. Dr. Shigeo Hino and his group in Nagasaki conducted intensive fieldwork regarding the mother-to-infant infection. Carrier mothers in Japan have been instructed to refrain from breastfeeding or modify the feeding procedures to prevent HTLV-1 infection. There is convincing evidence that HTLV-1 can be transmitted from individual to individual by sexual contact, especially males to females, and also through blood transfusions. All blood donated at the Red Cross Blood Centers in Japan has been subjected to HTLV-1 antibody testing beginning in November 1986.Treatment of ATL is the most difficult task. Dr. Masanori Shimoyama in Tokyo has organized a multicenter study group for the chemotherapy of ATL. Many other trials have been reported: deoxycoformycin, α-interferon combined with azidothymidine, and so on. The use of humanized monoclonal antibodies against the interleukin-2 receptor has been championed by Dr. Waldmann's group. More recently, successful allogeneic bone marrow transplantation for patients with ATL has been reported from many institutions.th International Conference of Human Retrovirology held in Kumamoto on May 11–13, 1992.Before my retirement from Kumamoto University in 1996, I edited a book titled "Adult T-cell Leukaemia" . Many ofA companion article by Robert C. Gallo recollects the events surrounding the discovery of the first human retrovirus, HTLV-I .


The incidence of breast cancer in young women (age < 35) is low. The biology of the disease in this age group is poorly understood, and there are conflicting data regarding the prognosis for these women compared to older patients.We retrospectively analyzed 2040 consecutive primary invasive breast cancer patients who underwent surgical procedures at our institution between 1990 and 1999. The younger age group was defined as patients aged <35 years at the time of diagnosis. The clinicopathological characteristics and treatment outcomes were compared between younger and older age groups.A total of 256 (12.5%) patients were aged <35. There was a significantly higher incidence of nuclear grade 3 and medullary histological-type tumors in younger patients compared to older patients. Axillary lymph node status, T stage, histological grade, c-erbB2 expression and estrogen receptor status did not differ significantly between the two age groups. Younger patients had a greater probability of recurrence and death at all time periods. Although there was no significant difference in disease-free survival between the two age groups in lymph node-negative patients, the younger group showed worse prognosis among lymph node-positive patients (p < 0.001). In multivariate analysis, young age remained a significant predictor of recurrence (p = 0.010).Young age (<35) is an independent risk factor for relapse in operable breast cancer patients. Breast cancer is relatively rare in women less than 35 years of age, with this group accounting for less than 4% of the total number of breast cancer cases diagnosed in Western countries ,2. DespiIt remains controversial whether young age at diagnosis is an adverse prognostic factor in primary breast cancer. While some studies have found that younger patients have worse clinical outcomes than older patients -7, otherBreast cancer is the most frequent cancer in Korean women and its incidence is increasing . Breast The aim of the present study was to retrospectively investigate clinicopathological characteristics and prognosis in a large, ethnically homogeneous group of young breast cancer patients (less than 35 years old) treated with the same strategy at a single institution.A retrospective review was performed of the medical records of all consecutive primary invasive breast cancer patients (not including phyllodes tumor) undergoing curative surgery in the Department of Surgery, Seoul National University Hospital between January 1990 and December 1999. Patients with distant metastasis detected at the time of surgery or within 4 months of surgery were excluded. Those patients whose surgical margins were positive for malignancy were also excluded. Patients' records were reviewed for the following: age of onset, family history of breast cancer in 1st or 2nd degree relatives, histological type of cancer, tumor size in pathology reviews, axillary lymph node status, histological grade (HG: Scarff-Bloom-Richardson classification), nuclear grade (NG: Black's nuclear grade), type of surgical procedure and adjuvant therapy administered. Disease was staged according to the American Joint Committee of Cancer (AJCC) system . The 'yo2 test (Pearson statistic) was used to determine the differences in clinicopathological features between the two groups of patients. The follow-up duration was calculated from the date of diagnosis until the date of death or last contact. The disease-free survival was the time between diagnosis and confirmation of disease recurrence. The overall survival was the time between diagnosis and death as a result of any cause, regardless of recurrence events. Survival estimates were computed using the Kaplan-Meier method [The χr method  and the r method . Multivar method . All stast or 2nd degree relatives, T stage, histological grade, c-erbB2 expression, nor ER or PR status were different between the two groups  were aged <35 at the time of diagnosis. The median follow-up was 74 months. Histology showed the incidence of medullary carcinoma was significantly higher than ductal carcinoma in the younger group (p = 0.018). There was a significantly higher incidence of nuclear grade 3 in the younger group than in the older group (p = 0.015). Axillary lymph node status, the most prominent prognostic factor in breast cancer, was not significantly different between the two age groups. Also, neither the family history of breast cancer in 12.5% wereThe proportion of breast-conserving surgery compared to mastectomy was similar in both groups. Axillary lymph node dissection, at least to the first Berg level , was perp < 0.001). At 5 years, the actuarial recurrence rate for patients <35 years old was 30.4% as compared with 18.7% for older patients. This difference persisted at 10 years, at which time the actuarial recurrence rates were 40.1% and 28.6%, respectively. Overall survival among younger patients was significantly worse than for older patients . The 5-year survival rate was 80.0% for patients aged <35 years as compared with 88.5% for older patients. Stratified analysis according to axillary lymph node status was performed for disease-free survival. In lymph node-negative patients there was no significant difference in disease-free survival between the two age groups . However, in lymph node-positive patients, disease-free survival was significantly worse in younger patients .Younger patients had a worse disease free survival (greater probability of recurrence) at all time periods . However, young age was not a significant independent predictor of overall survival in the same Cox model . Because hormone therapy was done more frequently in older patients than young age group  remained a significant predictor of recurrence when entered into a model containing all potential demographic, pathologic and immunohistochemical variables (Table 5 years rOur results showed that operable young breast cancer patients (<35 years old) have a worse prognosis than older patients in terms of both overall survival and recurrence. The difference in disease-free survival was clear in patients with axillary lymph node metastasis, but was not observed in lymph node-negative patients. Even after controlling for differences in distribution of potential prognostic factors, young age remained a significant predictor of recurrence.The present findings support previous reports showing that women diagnosed with breast cancer at a younger age have a poorer prognosis compared with their older counterparts -7. HowevTo our knowledge, the present study is the largest to directly compare the prognosis of younger (<35) breast cancer patients with that of their older counterparts. Moreover, the data in this study were generated from patients of the same ethnicity undergoing treatment at a single institution under the same contemporary strategy of surgery and adjuvant therapy over a relatively short time period (10 years). In addition, this study included a multivariate analysis of the difference in distribution of potential prognostic markers between the two age groups.The biomarker results in the present study are different to those reported for other populations, including ethnically-related Asian patients. In a study of 1052 Chinese breast cancer patients in Hong Kong, 53% and 61.6% of pre- and postmenopausal women were ER-positive, respectively, and 51.5% and 46.2% were PR-positive, respectively . Those fAlthough not a major focus of this study, we found PR and c-erbB2 expression were significant independent predictors of disease recurrence. Currently, the role of PR status as a prognostic factor is not clear, with some evidence to suggest it is useful ,27 and oThe St. Gallen Consensus Conferences in 1998 and 2001 concluded that age under 35 was a high risk factor for relapse in node-negative breast cancer patients ,33. KromIt has been suggested that younger women with breast cancer have a poorer prognosis because they present with later stage disease due to either physician or patient delay in diagnosis. However, in this study, no significant difference was found between the two age groups in terms of tumor size or lymph node status. Moreover, multivariate analysis indicated that young age is an independent negative prognostic factor. This issue of delayed diagnosis is not conclusive now and should be elucidated further in subsequent studies.p = 0.008). Although we did not have full information on each patient's menopausal status at the time of diagnosis, this result suggests that patients under 35 years have even worse prognosis than relatively "less young age" premenopausal patients.One possible limitation of this study is that the control group was heterogeneous and contained a mixture of premenopausal and postmenopausal patients. Adami et al. showed complex pattern of survival as a function of age at diagnosis of breast cancer . Howeverst degree relatives. We found four BRCA2 and one BRCA1 mutations that are thought to be disease-causing (data not shown). Only one of these 5 patients was less than 35 years old at the time of cancer development. It is known that young breast cancer patients are more likely to have an inherited form of the disease [Up to 15–30% of women aged less than 35 years diagnosed with breast cancer are likely to have germ-line BRCA1 or BRCA2 mutations . Althoug disease . However disease .Although most current breast cancer investigators agree that young age is an adverse prognostic factor for breast cancer, there have been few studies designed to elucidate the molecular or genetic differences associated with young age breast cancer. Recent CGH (Comparative Genomic Hybridization) analysis suggested that alterations in specific regions on chromosomes might be responsible for the poor outcome of early onset breast cancer . Future These results show that operable young breast cancer patients (<35 years old) have a worse prognosis than older patients in terms of both overall survival and recurrence. Even after controlling for differences in distribution of potential prognostic factors, young age is an independent predictor of recurrence. The underlying biology of young age breast cancer needs to be elucidated and development of tailored treatment for this patient population is crucial.The author(s) declare that they have no competing interests.WH selected cases, reviewed medical records, analyze data, and drafted the manuscript. SWK participated in the data collection and input. IAP carried out the pathological diagnosis and immunohistochemistry. DK performed the statistical analysis. SWK, YKY, SKO, KJC, and DYN conceived of the study, and participated in its design and coordination. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:


Health food stores have long hawked fish oil capsules as a cure-all for everything from migraines to heart disease. And though such claims are often weak on scientific evidence, fish oil, it turns out, is no snake oil. A recent review of scientific studies concludes that omega-3 fatty acids can indeed protect against heart disease, and the American Heart Association now recommends fish oil capsules for patients with coronary heart disease.Fatty acids come in hundreds of varieties, distinguished primarily by their structure, which in turn determines their physiological role. Unlike proteins or genes—which are polymers made up of amino acids and nucleotides, respectively—fatty acids are a large group of compounds containing long chains of carbon and hydrogen atoms with a carboxylate group (acid) attached at the end. It is this asymmetrical chemical configuration that gives fatty acids their unique properties. Fatty acid diversity comes from variations in the length of the carbon chain and in the number of double bonds between carbons. Fatty acids with one or more double bonds are called unsaturated fatty acids.PLoS Biology, Marina Kniazeva et al. explore the origin and function of mmBCFAs in the worm Caenorhabditis elegans and find that these relatively obscure fatty acids play a crucial role in growth and development.Fatty acids play an essential role in metabolism, providing the cell with a concentrated source of energy, and form the structural foundation of the cell membrane, where they are most conspicuous and perhaps best understood. Long-chain (unbranched) fatty acids, which run ten to 22 carbons long, are the most common fatty acids in animal cells and the most studied. One much less understood class of fatty acids—the monomethyl branched-chain fatty acids (mmBCFAs)—has been found in organisms from bacteria to humans, but its role remains obscure. In this issue of elo-5 and elo-6.mmBCFAs are abundant in diverse genera of bacteria, which use a supply of branched-chain amino acids and enzymes to assemble the fatty acid chains. mmBCFA biosynthesis has been characterized in bacteria, but not in eukaryotes.  Here, Kniazeva et al. identified worm genes that are homologous to the gene that codes for an enzyme called elongase in another eukaryote, yeast. Elongases are enzymes that extend the length of fatty acid chains by two carbons. To see what kind of fatty acid molecules the homologous worm genes were synthesizing, the authors used a technique called RNA interference (RNAi) to “silence” the genes' expression in the worms. Surprisingly, two of the eight inhibited genes had a specific effect on branched-chain fatty acid levels: elo-5 function had deleterious effects on the growth and development of the worms. The progeny of worms treated as embryos with RNAi for elo-5 stopped growing at the first larval stage, while the progeny of worms treated at later stages developed to adulthood but got progressively sicker and showed reproductive problems. These defects were corrected when the researchers fed the mmBCFAs directly to the worms, indicating that these mmBCFAs are essential for normal larval growth and development.Inhibiting Given the widespread distribution of mmBCFAs in organisms as diverse as bacteria and humans, it's perhaps not too surprising that they regulate essential physiological functions during animal development. It's still not clear, however, what all the components of the fatty acid manufacturing machinery are or how an organism monitors production levels. And though it's still an open question as to how these ubiquitous molecules function in mammals, the fact that they have been conserved throughout evolution underscores their importance—and suggests they may play a similar role.


Concerns regarding the privacy of health information are escalating owing both to the growing use of information technology to store and exchange data and to the increasing demand on the part of patients to control the use of their medical records. The objective of this study was to evaluate the Health Care Information Directive (HCID), a recently-developed patient decision aid that aims to delineate the level of health information an individual is willing to share.We convened a series of four focus group meetings with several communities in a large Canadian city. A total of 28 men and women participated, representing health care consumer advocates, urban professionals, senior citizens, and immigrants who speak English as a second language. Data were analysed using qualitative methods.Participants lacked substantial knowledge regarding the fate and uses of personal health information. They expressed mistrust concerning how their information will be used and protected. Several suggestions were made towards customizing the use of data according to specific needs rather than broad and full access to their charts. Furthermore, despite concern regarding the implementation of a tool like the HCID, participants were hopeful that a refined instrument could contribute to the improved regulation of health information.This study indicated poor knowledge concerning the uses of personal health information, distrust concerning security provisions, and cautious support for a patient decision aid such as the HCID to improve control over health data. What do people know about what they can get access to, what they can ask for, and what they can expect? I think the majority of the population have no idea of what they can ask for and expect to get." (CA-4)Participants' accounts clearly suggested an absence of patient control over the collection, use, and disclosure of PHI. No participants recalled having ever been consulted about how their information was to be used. A great deal of concern was voiced about the extent to which health data appears to be freely accessible to a wide variety of users: "Lawyers, psychologists, social workers, researchers, pharmaceutical companies. Where does it stop?" (UP-4). In the course of describing how they feel about the issue of health privacy, participants repeatedly used terms such as "scary" and "horrifying":"I'm scared to guess who has [access to my health information]. It looks so easy for a lot of people to have access. That's the scary part of it. Maybe your employer can have access to your files, too. I don't know, that's just a guess." (IM-6)The majority of participants expressed concern that their PHI is not adequately safe-guarded and that the implementation of a tool such as the Health Care Information Directive would not result in significantly enhanced privacy or increased security. There was a widespread view that too much data is currently made available when only specific details are required. Doubts were raised about how consent for one specific use only would be managed:"What's going to prevent any leaking from one of these [uses] into the others? ... It just seems to me that if there's information on-line, things are going to be compromised. You know, people make a living doing that stuff. The more they find out about you, the more you can be exploited. It's that simple. These systems, they're not secure yet, and I don't know if they can ever be secure." (UP-3)Health privacy concerns related to the security of electronic databases and the Internet were shared by others:"We've all heard stories where there's been stolen identities. How difficult is it for the victim to get his or her own identity back? Same idea. Where does it end? Where does it stop? Who's got what information? How am I going to protect myself?" (UP-6)Participants suggested a number of other mechanisms that could work in conjunction with the HCID to enhance security and facilitate individual control over PHI. One such mechanism would be an online real-time audit system in which the details of all accesses to an individual's PHI are recorded and made available to those wishing to track access to their PHI over time. Also, the idea of a health data ombud was raised in several groups and received a great deal of support.Issues related to trust were raised in each of the four groups. Participants of all ages and socioeconomic status expressed feelings of mistrust in relation to the protection of their privacy and the security of their PHI. A great many participants spoke of how their past experiences with the health care system have fostered significant mistrust and suspicion where their right to privacy is concerned. These accounts revealed a growing distress that large corporations have too much access to and influence on government programs, especially in contrast to the access and influence accorded to patients:"What about the rights of the patient? Let's say I'm the patient. What kind of power do I have? Let's say this [the HCID] was created next year. What power does the patient have to make sure any of this is happening? To me, a pharmaceutical company is way more powerful than the patient." (CA-2)Others were even more sceptical, questioning the trustworthiness of the basic tenets of the model upon which the HCID is based:"By filling this out, I'm buying into the concept of sharing information, but I don't have any faith that it can be kept private.... It will spill, it will bleed, it will flow. So I'm distrustful of the whole thing. This just sets up more spilling and more flowing. If I fill out a form like this, then I'm validating the process, which I don't really trust." (UP-8)While the majority were sceptical that the HCID would prevent all breaches of privacy, there was a general consensus that it would serve to enhance significantly the security of health data. One participant noted that the proposed decision aid may also serve a useful purpose as "a sort of consciousness raising" tool. Other impressions varied from "it has some potential" to "it is a great step forward." Reactions were mixed in response to the question of whether the HCID will be successful in empowering individuals and increasing the amount of control over PHI:"I'm very dubious as to whether this matrix will be useful because of the difficulty people will have filling it out. In spite of that, I think the idea has merit and principle. There's merit in what you're trying to do, but I don't think that this is going to succeed." (CA-5)"I guess the reality is our information will be shared, so we might as well get on the bandwagon with regulating it and controlling it... You can't stop it from being shared, so maybe you can influence how it will be shared." (UP-2)Despite the weaknesses and limitations of the present version of the directive, one participant neatly summarized the view of the majority of participants regarding the utility of the HCID or some such tool: "Not having it allows total absence of control, therefore it is a necessary evil." (CA-4).Participants provided numerous suggestions regarding the formatting of the HCID in order to facilitate implementation. Ideas ranged from simplifying the language and providing definitions of technical terms to modifying the layout and shading those areas where there is no discretion :"Maybe you've got too many columns.... Well, maybe you're trying to do too many different things at once." (CA-4)"This is too busy, it's too much. If I'm sick, I friggin' don't want to be bothered with it.... Look at this. English is my first language. How would somebody whose mother tongue is something other than English? It's too complicated." (SC-1)"I think people tend to say 'no' for things that are not clear. I would say 'yes' if I knew what it means exactly, but I don't know, so I don't want to take a chance." (IM-1)To address the complexity issue, suggestions were made concerning the need to provide a customer service representative either in a health clinic or via a toll-free helpline for assistance with completing the HCID.Across the four groups, there was great variability in the preferred mode of implementation. The preference among participants in the health advocates and urban professional groups was for an on-line implementation format. In contrast, the majority of the senior citizens and immigrants preferred other options, the former favouring a postal format and the latter the primary care setting. As one senior citizen remarked: "I prefer the doctor's office. I wouldn't fill it and send it back through the mail, no." (SC-3)British Medical Journal suggested that perhaps patients should be asked whether certain items of their medical chart should only be shared with specified individuals or organizations or only for pre-determined purposes [A recent editorial in the purposes . This paStudy participants lacked substantial knowledge regarding the fate and uses of PHI within a publicly-funded health care system. Participants expressed mistrust concerning how their PHI is used and safe-guarded. Several suggestions were made towards customizing the use of data according to specific needs rather than broad and full access to their charts. Furthermore, concerns were expressed regarding the implementation of a tool such as the HCID. Nevertheless, there was hope that a refined instrument could contribute to improved data management and regulation and enhanced privacy protection.Although this study reports on a small sample from a single large urban centre, the focus group participants were drawn from various different niches of Canadian society. This sampling strategy allowed us to explore a broad range of experiences and perspectives; however, further testing and evaluation are required. Ultimately, it will be necessary to evaluate the tool using a representative sample of patients who complete the HCID in a 'live' test of its feasibility.Our findings underscore the difficulties involved in accessing health care data for research and other secondary purposes. Participants acknowledge the myriad benefits derived from the use of health data; however, distrust, lack of respect, and insufficient patient control of the process threaten to undermine these very benefits. This finding has been previously reported by Willison and associates in Canada  and by RParticipants appreciated the benefits accorded by a tool such as the HCID. As opposed to forms of blanket consent or other opt in/opt out models, the possibility of exerting greater control over one's PHI was attractive. The participants provided concrete suggestions for improving the format and content of the HCID. It is evident that any method to enhance control of health information via explicit consent requires description of the various forms the data may take, the specific purposes for which the data would be used, and the various channels of the health care system through which the data might flow. To our knowledge, such detailed data flowmaps for PHI do not exist in Canada, although they have been laid out in Great Britain . A modelAn intriguing finding was the appeal of an online data audit system. Possessing the ability to monitor who has accessed their PHI and for what purposes raises the possibility of additional strategies that could empower individuals to control the fate of their health information. This finding has also been verified by Pyper and colleagues  and was Finally, there is a distinction to be made between using the HCID to enforce the will of the patient versus its use as a documentation tool. Our vision is that the HCID will, ultimately, serve both of these important functions; further follow-up evaluation of a revised model of the HCID using a larger sample (comprised of patients as well as providers) is needed to address this distinction. As with any patient decision aid or empowerment tool, documenting the preference of the patient is only meaningful and useful to the extent that the documented preferences are known and ultimately acted upon by those providing care. We believe the present data illustrate the critical problem of mistrust that currently exists. Indeed, this is one of the greatest challenges to be overcome in the continuing development and validation of this tool.This study indicated poor knowledge concerning the uses of health data, distrust concerning current security provisions, and qualified support for a tool such as the HCID to improve patient control over health information. On the basis of this evaluation, the HCID will be revised significantly, including the addition of an educational component, and then submitted to further evaluation. The creation of data flowmaps and the exploration of audit functions and governance structures are strongly recommended as avenues for future research.None declared.CST participated in the collection, analysis, and interpretation of the data and is the primary author of the paper. GCD recruited the participants, moderated the focus group meetings, participated in the data analysis, and contributed to the editing and revising of the paper. REGU initiated and designed the study, participated as a reliability check in the process of data analysis, and contributed to the editing and revising of the paper. As principal investigator, he will act as guarantor. All authors have read and approved the final version of the paper.1. What is your understanding of the term 'personal health information'?2. Who do you believe has access to your personal health information?3. Do you believe that consent should be required to access your personal health information?1. What is your first impression of the Health Care Information Directive?2. Is it clear?3. Is it self-explanatory?1. How useful do you believe the Health Care Information Directive would be in practice?2. Is it user-friendly?3. What kind of changes would you suggest?1. How feasible is the application of the Health Care Information Directive?2. Who should present it to the patient?3. When should it be presented to the patient?1. What are the potential gains of the Health Care Information Directive?2. What are the potential harms?3. Does it adequately protect privacy and confidentiality?The pre-publication history for this paper can be accessed here:


Mycobacterium tuberculosis causes tuberculosis (TB) in people, and related species that infect other animals are used as model systems for the study of TB. Much progress has been made in identifying the armaments (or virulence factors) of the bacteria. But the interplay, or chess match, between the bacterium and the animal it infects is much less clear. One of the host's first moves against the mycobacterium is the formation of a granuloma. Granulomas are tightly aggregated structures that consist of macrophages—one of the first lines of defense of the immune system—within which the infecting bacterium grows. Besides these and related cells that are present at the site of infection, additional macrophages and other immune cells are recruited in the formation of the granuloma. Although granulomas are required for the elimination of the infection, Lalita Ramakrishnan and colleagues have now shown that the bacteria have a game plan of their own.Fighting an infection might seem to be a battle between David and Goliath, given the relative sizes of bacterial infectious agents and the animals they infect. But on closer examination it is more often a chess match between two skilled opponents who have the uncanny ability to anticipate each other's moves. M. marinum. This enables the researchers to watch cells as they are recruited into the granuloma.One problem in understanding the interaction between the mycobacterium and the host has been that it occurs deep in the lung of the infected animal, which makes it difficult to analyze how each of the animal or bacterial factors affect the strategic interplay between the host and pathogen. To overcome this limitation, Ramakrishnan and colleagues used zebrafish embryos, which are transparent and can be infected by a relative of the TB pathogen, M. bovis that is used as an attenuated TB vaccine. But the precise role of RD1 in infection remains obscure.Some of the virulence factors of mycobacteria are encoded in an area of the genome called the RD1 locus. In a mouse model, a strain of the bacteria missing RD1 causes far less pathology than a strain with the full complement of genes. The RD1 locus is also absent in the bacterial strain M. marinum and a strain with an RD1 deletion, Ramakrishnan and colleagues have observed that RD1 is actually required for granuloma formation but isn't needed for the bacteria to infect macrophages. What's more, macrophages that are infected with mycobacteria that contain RD1 produce a signal that further recruits macrophages to granulomas. This might seem an odd virulence strategy, as macrophages are required for mycobacterial elimination. But in this ongoing chess match, the virulent mycobacterium exploits the host's defense—granuloma formation—by providing additional macrophages for the bacteria to infect.By visualizing in zebrafish infections of a virulent strain of The end game of the chess match remains unclear. While granulomas are required for protection against mycobacteria, they are not completely effective. Thus, these bacteria have developed a strategy to recruit the normally defensive cells of the host to their advantage, but it remains to be shown what tips the balance between the macrophages' ability to clear the infection and their unwitting participation in the development of TB.