Integrative Metatranscriptomic Analysis Reveals Disease-specific Microbiome-host Interactions in Oral Squamous Cell Carcinoma.

Studies on the microbiome of oral squamous cell carcinoma (OSCC) have been limited to 16S rRNA gene sequencing. Here, laser microdissection coupled with brute-force, deep metatranscriptome sequencing was employed to simultaneously characterize the microbiome and host transcriptomes and predict their interaction in OSCC. The analysis involved 20 HPV16/18-negative OSCC tumor/adjacent normal tissue pairs (TT and ANT) along with deep tongue scrapings from 20 matched healthy controls (HC). Standard bioinformatic tools coupled with in-house algorithms were used to map, analyze, and integrate microbial and host data. Host transcriptome analysis identified enrichment of known cancer-related gene sets, not only in TT versus ANT and HC, but also in the ANT versus HC contrast, consistent with field cancerization. Microbial analysis identified a low abundance yet transcriptionally active, unique multi-kingdom microbiome in OSCC tissues predominated by bacteria and bacteriophages. HC showed a different taxonomic profile yet shared major microbial enzyme classes and pathways with TT/ANT, consistent with functional redundancy. Key taxa enriched in TT/ANT compared with HC were Cutibacterium acnes, Malassezia restricta, Human Herpes Virus 6B, and bacteriophage Yuavirus. Functionally, hyaluronate lyase was overexpressed by C. acnes in TT/ANT. Microbiome-host data integration revealed that OSCC-enriched taxa were associated with upregulation of proliferation-related pathways. In a preliminary in vitro validation experiment, infection of SCC25 oral cancer cells with C. acnes resulted in upregulation of MYC expression. The study provides a new insight into potential mechanisms by which the microbiome can contribute to oral carcinogenesis, which can be validated in future experimental studies. Significance: Studies have shown that a distinct microbiome is associated with OSCC, but how the microbiome functions within the tumor interacts with the host cells remains unclear. By simultaneously characterizing the microbial and host transcriptomes in OSCC and control tissues, the study provides novel insights into microbiome-host interactions in OSCC which can be validated in future mechanistic studies.

DNA polymerase θ protects leukemia cells from metabolically induced DNA damage.

Leukemia cells accumulate DNA damage, but altered DNA repair mechanisms protect them from apoptosis. We showed here that formaldehyde generated by serine/1-carbon cycle metabolism contributed to the accumulation of toxic DNA-protein crosslinks (DPCs) in leukemia cells, especially in driver clones harboring oncogenic tyrosine kinases (OTKs: FLT3(internal tandem duplication [ITD]), JAK2(V617F), BCR-ABL1). To counteract this effect, OTKs enhanced the expression of DNA polymerase theta (POLθ) via ERK1/2 serine/threonine kinase-dependent inhibition of c-CBL E3 ligase-mediated ubiquitination of POLθ and its proteasomal degradation. Overexpression of POLθ in OTK-positive cells resulted in the efficient repair of DPC-containing DNA double-strand breaks by POLθ-mediated end-joining. The transforming activities of OTKs and other leukemia-inducing oncogenes, especially of those causing the inhibition of BRCA1/2-mediated homologous recombination with and without concomitant inhibition of DNA-PK-dependent nonhomologous end-joining, was abrogated in Polq-/- murine bone marrow cells. Genetic and pharmacological targeting of POLθ polymerase and helicase activities revealed that both activities are promising targets in leukemia cells. Moreover, OTK inhibitors or DPC-inducing drug etoposide enhanced the antileukemia effect of POLθ inhibitor in vitro and in vivo. In conclusion, we demonstrated that POLθ plays an essential role in protecting leukemia cells from metabolically induced toxic DNA lesions triggered by formaldehyde, and it can be targeted to achieve a therapeutic effect.

TET2 and DNMT3A Mutations Exert Divergent Effects on DNA Repair and Sensitivity of Leukemia Cells to PARP Inhibitors.

Somatic variants in TET2 and DNMT3A are founding mutations in hematological malignancies that affect the epigenetic regulation of DNA methylation. Mutations in both genes often co-occur with activating mutations in genes encoding oncogenic tyrosine kinases such as FLT3ITD, BCR-ABL1, JAK2V617F , and MPLW515L , or with mutations affecting related signaling pathways such as NRASG12D and CALRdel52 . Here, we show that TET2 and DNMT3A mutations exert divergent roles in regulating DNA repair activities in leukemia cells expressing these oncogenes. Malignant TET2-deficient cells displayed downregulation of BRCA1 and LIG4, resulting in reduced activity of BRCA1/2-mediated homologous recombination (HR) and DNA-PK-mediated non-homologous end-joining (D-NHEJ), respectively. TET2-deficient cells relied on PARP1-mediated alternative NHEJ (Alt-NHEJ) for protection from the toxic effects of spontaneous and drug-induced DNA double-strand breaks. Conversely, DNMT3A-deficient cells favored HR/D-NHEJ owing to downregulation of PARP1 and reduction of Alt-NHEJ. Consequently, malignant TET2-deficient cells were sensitive to PARP inhibitor (PARPi) treatment in vitro and in vivo, whereas DNMT3A-deficient cells were resistant. Disruption of TET2 dioxygenase activity or TET2-Wilms' tumor 1 (WT1)-binding ability was responsible for DNA repair defects and sensitivity to PARPi associated with TET2 deficiency. Moreover, mutation or deletion of WT1 mimicked the effect of TET2 mutation on DSB repair activity and sensitivity to PARPi. Collectively, these findings reveal that TET2 and WT1 mutations may serve as biomarkers of synthetic lethality triggered by PARPi, which should be explored therapeutically. SIGNIFICANCE: TET2 and DNMT3A mutations affect distinct DNA repair mechanisms and govern the differential sensitivities of oncogenic tyrosine kinase-positive malignant hematopoietic cells to PARP inhibitors.

The Polygenic and Monogenic Basis of Blood Traits and Diseases.

Blood cells play essential roles in human health, underpinning physiological processes such as immunity, oxygen transport, and clotting, which when perturbed cause a significant global health burden. Here we integrate data from UK Biobank and a large-scale international collaborative effort, including data for 563,085 European ancestry participants, and discover 5,106 new genetic variants independently associated with 29 blood cell phenotypes covering a range of variation impacting hematopoiesis. We holistically characterize the genetic architecture of hematopoiesis, assess the relevance of the omnigenic model to blood cell phenotypes, delineate relevant hematopoietic cell states influenced by regulatory genetic variants and gene networks, identify novel splice-altering variants mediating the associations, and assess the polygenic prediction potential for blood traits and clinical disorders at the interface of complex and Mendelian genetics. These results show the power of large-scale blood cell trait GWAS to interrogate clinically meaningful variants across a wide allelic spectrum of human variation.

Mechanical response of human female breast skin under uniaxial stretching.

Skin is a complex material covering the entire surface of the human body. Studying the mechanical properties of skin to calibrate a constitutive model is of great importance to many applications such as plastic or cosmetic surgery and treatment of skin-based diseases like decubitus ulcers. The main objective of the present study was to identify and calibrate an appropriate material constitutive model for skin and establish certain universal properties that are independent of patient-specific variability. We performed uniaxial tests performed on breast skin specimens freshly harvested during mastectomy. Two different constitutive models - one phenomenological and another microstructurally inspired - were used to interpret the mechanical responses observed in the experiments. Remarkably, we found that the model parameters that characterize dependence on previous maximum stretch (or preconditioning) exhibited specimen-independent universal behavior.

Oral lesions associated with nevirapine-related Stevens Johnson syndrome: A report of four cases.

Nevirapine is a non-nucleoside reverse transcriptase inhibitor, widely used in combination with other antiretroviral agents for treatment of HIV infection. Steven Johnson syndrome (SJS) is the major toxicity of nevirapine. We describe here four cases of SJS in HIV seropositive patients following nevirapine therapy. In all four cases cutaneous hypersensitivity reaction was seen with extreme oral lesions, three patients presented clinically with elevated liver enzymes and hepatitis, and two patients had ocular involvement.

Cardiac arrest caused by undersensing of a temporary epicardial pacemaker.

The R-on-T phenomenon is a well-known entity that predisposes to dangerous arrhythmias. Typically, a premature ventricular complex occurring at the critical time during the T wave of the preceding beat precipitates ventricular tachycardia and fibrillation. This phenomenon can occur not only in asynchronous ventricular pacemakers, but also in synchronous pacemakers, if loss of sensing of the intrinsic rhythm becomes evident. A patient who was fitted with a temporary epicardial wire, following cardiac surgery and experienced repeated episodes of polymorphic ventricular tachycardia caused by the R-on-T phenomenon, is described.

Psychotherapy in Brunei Darussalam.

Clinical psychologists face unique challenges in developing Southeast Asian countries because mental health care has not received the kind of attention it deserves. In part, this has been the result of lack of knowledge or misunderstanding about mental health and adherence to various religious and traditional beliefs. In this article, the practice of psychotherapy in Brunei Darussalam is reviewed and then illustrated with a typical case, Mrs. A. Asian psychotherapists need more comprehensive knowledge of prevailing cultural beliefs and religious practices among multiethnic population groups.

Relationship between Type A and B personality and debrisoquine hydroxylation capacity.

AIM: A person with Type A personality is an 'aggressor' compared with the rarely harried Type B. Although debrisoquine hydroxylase (CYP2D6) capacity has been associated with personality, no study has specifically investigated its association with personality Type A and B. Therefore the aim of this research was to study the impact of CYP2D6 on Type A and B personality. METHODS: Type A and B personality questionnaires were administered to 48 healthy patients undergoing elective orthopaedic surgery. After obtaining informed consent, patients were genotyped for the various CYP2D6 alleles by allele-specific polymerase chain reaction. Based on the genotypes, patients were grouped as extensive metabolizer (EM)1 (normal) (CYP2D6*1/*1), EM2 (intermediate) (CYP2D6*1/*4, CYP2D6*1/*5, CYP2D6*1/*9 and CYP2D6*1/*10) and EM3 (slow) (CYP2D6*4/*10, CYP2D6*5/*10, CYP2D6*10/*10 and CYP2D6*10/*17). Chi(2) was used to determine the relationship between the groups and personality types. RESULTS: The percentages of patients who were of the EM1, EM2 and EM3 groups were 20.8%, 52.1% and 27.1%, respectively. There was a significant difference (P = 0.032) between the three groups in terms of personality type, in which EM1 showed a tendency to be of personality Type A while EM2 and EM3 tended to be of personality Type B. CONCLUSION: The study suggests that there is a relationship between CYP2D6 activity and Type A and B personality.

Outcome of children with traumatic brain injury in rural Malaysia.

Malaysia had the second highest crude accident rate in the world until 1998. Most children who were involved in these road traffic accidents required intensive neurosurgical care management. We report a prospective study on 36 paediatric neurotrauma patients in rural North East West Malaysia who underwent uniform intensive therapy and were subsequently followed up over a period of 2 years. The modified paediatric Glasgow Coma Scale with support of the revised Wechlser Intelligence Scale for children was used to test the outcome of these children over a period of two years. All patients were managed aggressively in our intensive care as well as our high dependency units. Our results indicate that improvement in outcome is seen after a six month period. Midline shift, duration of coma and duration of transport were found to be significant variables associated with bad outcome. Other variables i.e. age, sex, Glasgow Coma Scale on admission and on site, and lesions of the dominant lobe were not found to be associated with good outcome in these patients.

Real time analysis of the affinity regulation of alpha 4-integrin. The physiologically activated receptor is intermediate in affinity between resting and Mn(2+) or antibody activation.

This work examines the affinity of alpha(4)beta(1)-integrin and whether affinity regulation by G protein-coupled receptor (GPCR) and chemokines receptors is compatible with cell adhesion mediated between alpha(4)-integrin and vascular cell adhesion molecule-1. We used flow cytometry to examine the binding of a fluorescent derivative of an LDV peptide (Chen, L. L., Whitty, A., Lobb, R. R., Adams, S. P., and Pepinsky, R. B. (1999) J. Biol. Chem. 274, 13167-13175) to several cell lines and leukocytes with alpha(4)-integrin ranging from about 2,000 to 100,000 sites/cell. The results support the idea that alpha(4)-integrins exhibit multiple affinities and that affinity changes are regulated by the dissociation rate and conformation. The affinity varies by 3 orders of magnitude with the affinity induced by binding mAb TS2/16 plus Mn(2+) > Mn(2+) ' TS2/16 > activation because of occupancy of GPCR or chemokines receptor > resting receptors. A significant fraction of the receptors respond to the activating process. The change in alpha(4)-integrin affinity and the corresponding change in off rates mediated by GPCR receptor activation are rapid and transient, and their duration depends on GPCR desensitization. The affinity changes mediated by IgE receptor or interleukin-5 receptor persist longer. It appears that the physiologically active state of the alpha(4)-integrin, determined by inside-out signaling, has similar affinity in several cell types.

Impact of medical school experiences on senior medical students' interest in psychiatry.

This is a questionnaire study analyzing the influence of various medical school experiences on 146 final year medical students' interest and respect for psychiatry. The results indicated that clinical postings, lectures, contact with psychiatric patients and psychiatry faculty had a positive influence on majority of students. Many students perceived non-psychiatric faculty and fellow students as critical of psychiatry. Students with greater career interest in psychiatry were more positively influenced by contact with patients, faculty and clinical postings. When compared to results reported from developed nations, medical school experiences had a similar influence on our students. However, it is doubtful whether our findings can be generalized to other medical schools in Indian and further studies form other medical schools are warranted.

Senior medical students' attitude towards psychiatry : relationship with career interest.

Using the Senior Medical Student Questionnaire, the attitudes towards psychiatry and the career interest in psychiatry of 146 final year medical students were obtained. The results indicated that, on the overall merits of the field of psychiatry and role definition and functioning of psychiatrists, students had a favorable opinion. Many students considered that career and personal rewards in psychiatry are limited. Analysis of the relationship between career interest and attitudes showed that on many items students with a greater career interest in psychiatry had more favorable opinions. However, there was evidence to suggest that students with greater career interest in psychiatry were equally concerned about the low career and social rewards in psychiatry.

Prevalence of depressive symptoms among patients attending a general outpatient clinic.

Using both the English version and an Igbo translation of Zung's Self-rating Depression Scale (SDS), 132 first-time attenders to a hospital-based general outpatient clinic were screened for presence of depressive symptoms. The mean SDS index obtained for the whole sample fell within the normal range. However, a prevalence rate of 25% for depressive symptoms was obtained. 14% scored within the range for "mild depression", while 11% obtained scores within the range for "moderate depression". Only three patients were referred to the psychiatric outpatient clinic of the same hospital. The need for general physicians to be able to recognise the presence and significance of psychological symptoms in their patients is emphasized.

Socio-demographic factors of depressive illness among Nigerians.

The socio-demographic characteristics of 142 depressive patients seen for the first time at the Psychiatric Hospital, Enugu, were studied. Females (55%) outnumbered males (45%). While depressive neurosis occurred more commonly in those under 30 years of age, manic-depressive psychosis (MDP) depression was commoner among those over 30. Married status was commoner among female MDP depressives, but there was no significant difference regarding marital status among those with depressive neurosis. MDP depression occurred more often among rural dwellers while depressive neurosis was diagnosed more often among urban dwellers. Although the majority of patients had a low level of education, there were a significant number of students and housewives among those with depressive neurosis. The probable socio-cultural factors responsible for the observed differences are discussed. A suggestion is made for a central control and monitoring of all available alternative forms of treatment (orthodox, novel, traditional and spiritual) for a better mental health delivery.

Socio-economic status and mental disorder--profile of a Nigerian psychiatric inpatient population.

A study of the socio-economic and diagnostic profile of psychiatric patients treated at a mental hospital in Nigeria over a period of six months was conducted. Schizophrenia, organic psychosis, and mental sub-normality were found to have been diagnosed more often among under privileged persons from lower socio-economic classes; while affective disorder (manic depression) and neurotic illness were commoner among persons from economically more fortunate higher social classes. Males exceeded females in the cohort and the patients generally exhibited upward social mobility when compared with their parents. Possible socio-cultural factors contributing to the findings have been discussed. A suggestion is made for a more elaborate field work to study the relationship between socio-economic class and psychopathology in a developing country like Nigeria.

A psychosocial study of Igbo schizophrenic patients treated at a Nigerian psychiatric hospital.

A study of the sociodemographic and clinical characteristics of schizophrenics of Igbo origin treated at a psychiatric hospital in Nigeria over a period of 6 months was made together with a limited follow-up. Males exceeded females in the proportion of 2:1. About 66% were below the age of 30 years. While there were more married females than single, there were more single males than married. However, single persons on the whole predominated. The majority (61%) were either illiterate or had low education while 52% were either unemployed or unskilled persons. Paranoid and catatonic schizophrenias were the commonest diagnostic subgroups. The short-term prognosis was very good in that 96% were greatly improved at the time of discharge. There was, however, a high dropout rate of 57% over a period of 5 years. Of those still attending, 73% remained improved. The possible sociocultural basis of some of the findings is discussed.

A psychosocial study of schizophrenic patients treated at a Nigerian psychiatric hospital.

A study of the sociodemographic and psychological characteristics of schizophrenics treated at a psychiatric hospital in Nigeria over a period of six months was conducted along with a limited five-year follow-up. Male patients exceeded female (2:1) and 65.7 percent were below 30 years of age. Whereas there were more married female subjects than single, there were more single male subjects than married ones. However, single persons predominated. The majority (61.3 percent) either were illiterate or had low education and 52 percent were either unemployed or un-skilled. Paranoid and catatonic schizophrenia were the most common diagnostic subgroups. The short-term prognosis was very good in that 96.1 percent were greatly improved at the time of discharge. There was, however, a high default rate of 57.4 percent over a period of five years. Of those still attending, 73.5 percent remained improved. The sociocultural basis of some of the findings is discussed.

Socio-demographic factors of depressive disorders in India: a comparative appraisal.

Socio-demographic study of 173 cases of depression was carried out prospectively over one year's period from January 1977 to December 1977, at the psychiatric out-patient department of Kasturba Medical College Hospital, Manipal, Karnataka. The findings are compared with the data reported from other centres in India and the results are discussed.