Regulation of gastric carcinogenesis by Helicobacter pylori virulence factors

Helicobacter pylori is the strongest known risk factor for gastric adenocarcinoma, and strains that possess the cag secretion system, which translocates the bacterial effector CagA into host cells, augment cancer risk. H. pylori strains that express the vacuolating cytotoxin or the outer membrane protein OipA are similarly associated with severe pathologic outcomes. We previously reported that an in vivo adapted H. pylori strain, 7.13, induces gastric adenocarcinoma in rodent models of gastritis. In the current study, we used carcinogenic strain 7.13 as a prototype to define the role of virulence constituents in H. pylori-mediated carcinogenesis. Mongolian gerbils were infected with wild-type strain 7.13 or cagA(-), vacA(-), or oipA(-) mutants for 12 to 52 weeks. All infected gerbils developed gastritis; however, inflammation was significantly attenuated in animals infected with the cagA(-) but not the vacA(-) or oipA(-) strains. Gastric dysplasia and cancer developed in >50% of gerbils infected with either the wild-type or vacA(-) strain but in none of the animals infected with the cagA(-) strain. Inactivation of oipA decreased beta-catenin nuclear localization in vitro and reduced the incidence of cancer in gerbils. OipA expression was detected significantly more frequently among H. pylori strains isolated from human subjects with gastric cancer precursor lesions versus persons with gastritis alone. These results indicate that loss of CagA prevents the development of cancer in this model. Inactivation of oipA attenuates beta-catenin nuclear translocation and also decreases the incidence of carcinoma. In addition to defining factors that mediate H. pylori-induced cancer, these results provide insight into mechanisms that may regulate the development of other malignancies arising within the context of inflammatory states.

Randomized, dose-escalation study of SD/01 compared with daily filgrastim in patients receiving chemotherapy

PURPOSE

To explore the use of SD/01 (a polyethylene glycol-conjugated filgrastim shown in preclinical studies to have a prolonged half-life) in patients with chemotherapy-induced neutropenia.

PATIENTS AND METHODS

Thirteen patients with non-small-cell lung cancer were randomized to receive daily filgrastim (5 microg/kg/d) or a single injection of SD/01 (30, 100, or 300 microg/kg) 2 weeks before chemotherapy and again 24 hours after administration of carboplatin and paclitaxel. Pharmacodynamic, pharmacokinetic, and safety analyses were performed.

RESULTS

Peak serum concentrations of SD/01 and the duration of increased serum concentrations were dependent on the SD/01 dose. SD/01 concentrations remained increased longer in patients with chemotherapy-induced neutropenia. Prechemotherapy median absolute neutrophil counts (ANCs) in patients receiving SD/01 were increased in a dose-dependent fashion, with the duration of this effect also being dose dependent. After chemotherapy, median ANC nadirs were similar in the filgrastim cohort and the cohort receiving SD/01 30 microg/kg, with higher nadirs seen in the cohorts receiving SD/01 100 or 300 microg/kg. Dose-limiting toxicities were not noted. CD34(+) cells were mobilized in all cohorts.

CONCLUSION

A single dose of SD/01 increases the serum concentration of SD/01 for several days in a dose-dependent fashion and is not associated with significant toxicity. The effects of SD/01 on ANC and CD34(+) cell mobilization are comparable or greater than those achieved with daily filgrastim. The self-regulation of this molecule provides a potential therapeutic advantage in a variety of clinical settings associated with neutropenia.

Focal osteomalacia due to low-dose diphosphonate therapy in Paget's disease

Transiliac bone biopsies carried out on 13 patients with Paget's disease to evaluate the effects of low-dose diphosphonate (disodium etidronate) therapy showed focal osteomalacia in the 9 patients in whom post-therapy specimens were taken through pagetic bone. Active bone resorption persisted in 5 of these. A mineralisation defect not amounting to osteomalacia--ie, osteoid of increased thickness but of normal extent--was present in the 4 specimens taken through non-pagetic bone. Although 9 patients experienced symptomatic improvement, 2 suffered fissure fractures in affected lower limbs. In Paget's disease, the combination of osteomalacia and continuing active resorption within a lytic lesion may increase the risk of fracture in a weight-bearing bone. It is suggested that although disodium etidronate often provides effective pain relief it should be administered with caution until the optimum dose and duration of therapy are further evaluated.

The topography of primate retina: a study of the human, bushbaby, and new- and old-world monkeys

The distribution of ganglion cells has been studied in the retinas of four primates: the prosimian bushbaby, the New-World squirrel monkey, the Old-World crab-eating cynamolgous monkey, and the human. The sizes of ganglion cell somas were also measured at a number of retinal locations and compared with similar measurements in the cat retina to test for the presence in primates of retinal specializations such as the visual streak, and for gradients in retinal structure, such as that between temporal and nasal retina. In all four primates, ganglion cell somas in peripheral retina ranged considerably in diameter (6-16 micrometer in the bushbaby, 8-22 micrometer in the squirrel monkey, 8-23 micrometer in the cynamolgous monkey, 8-26 micrometer in the human). It seems likely that the strong physiological correlates of soma size which have been described among cat retinal ganglion cells and among the relay cells of the macaque lateral geniculate nucleus are generally present in primates. In all four primates, evidence was also obtained of a visual streak specialization; the isodensity lines in ganglion cell density maps were horizontally elongated, and small-bodied ganglion cells were relatively more common in the region of the proposed streak than in other areas of peripheral retina. However, the visual streak seems less well developed than in the cat; among the four primate species examined it was best developed in the bushbaby, at least as assessed by the shape of the isodensity lines. All four primates showed a clear foveal specialization, but this feature seemed least developed in the bushbaby. At the fovea, ganglion cells are smaller in soma size than in peripheral retina; they also seemed more uniform in size, although some distinctly larger cells persist in the human and bushbaby. Soma size measurements also provided evidence of a difference between nasal and temporal areas of peripheral retina comparable to that reported for the cat and other species. Thus the primate retinas examined show features, such as the foveal specialization, which seem unique to them among mammals. They also show features, such as nasal-temporal differences in ganglion cell size, and (though weakly developed) a visual streak, which they have in common with other mammals with widely different phylogenetic histories.

Ligand-dependent structural variations in Escherichia coli F1 ATPase revealed by cryoelectron microscopy

The Escherichia coli F1 ATPase, ECF1, has been examined by cryoelectron microscopy after reaction with Fab' fragments generated from monoclonal antibodies to the alpha and epsilon subunits. The enzyme-antibody complexes appeared triangular due to the superposition of three anti-alpha Fab' fragments on alternating densities of the hexagonally arranged alpha and beta subunits. The Fab' to the epsilon subunit superimposed on a beta subunit. A density was observed near the center of the structure in the internal cavity. The position of this central density with respect to peripheral sites was not fixed. Sorting of images of ECF1 labeled with the combination of three anti-alpha Fab' fragments plus an Fab' directed to the epsilon subunit gave three classes in each of which the central density was closest to a different beta subunit. The distribution of the central density among the three classes was measured for different ligand-binding conditions. When ATP was present in catalytic sites under conditions where there was no enzyme turnover (i.e., without Mg2+ present), there were approximately equal numbers of images in each of three classes. When ATP and Mg2+ were added and ATP hydrolysis was allowed to proceed, almost two-thirds of the images were in the class in which the central density was closest to the beta subunit superimposed by the epsilon subunit. We conclude that domains within the ECF1 structure, either the central mass or a domain including the epsilon subunit, move in the enzyme in response to ligand binding. We suggest that this movement is involved in coupling catalytic sites to the proton channel in the F0 part of the ATP synthase.

Bcl-2 oncoprotein positivity and high MIB-1 (Ki-67) proliferative rate are independent predictive markers for recurrence in prostate carcinoma

Predicting the clinical behavior of prostate carcinoma can be difficult; one approach is to identify molecular prognostic markers. We evaluated proliferative rate (MIB-1 antibody) and expression of bcl-2, p53, and retinoblastoma (pRB) proteins, which have cell cycle-related functions, in 208 consecutive radical prostatectomy specimens. Values were correlated with histopathologic parameters (Gleason tumor score, tumor amount, capsule invasion, and involvement of surgical margins, seminal vesicles, or lymph nodes) and with recurrence-free survival (4-year median follow-up). A high MIB-1 proliferative rate was associated with all of the measured histopathologic parameters, p53 overexpression with tumor amount, and pRB expression with positive lymph nodes. pRB and p53 expression levels were not associated with differences in recurrence-free survival. A high MIB-1 proliferative rate and bcl-2 positivity were associated with increased recurrence, both considered individually, and also independently and additively when examined together and with the most predictive histopathologic factors (Gleason tumor score and seminal vesicle involvement). MIB-1 proliferative rate and bcl-2 positivity may prove to be useful markers for poor prognosis in prostate carcinoma.

Dietary intake and risk factors for poor diet quality among children in Nova Scotia

OBJECTIVE

Public health policies promote healthy nutrition but evaluations of children's adherence to dietary recommendations and studies of risk factors of poor nutrition are scarce, despite the importance of diet for the temporal increase in the prevalence of childhood obesity. Here we examine dietary intake and risk factors for poor diet quality among children in Nova Scotia to provide direction for health policies and prevention initiatives.

METHODS

In 2003, we surveyed 5,200 grade five students from 282 public schools in Nova Scotia, as well as their parents. We assessed students' dietary intake (Harvard's Youth Adolescent Food Frequency Questionnaire) and compared this with Canadian food group and nutrient recommendations. We summarized diet quality using the Diet Quality Index International, and used multilevel regression methods to evaluate potential child, parental and school risk factors for poor diet quality.

RESULTS

In Nova Scotia, 42.3% of children did not meet recommendations for milk products nor did they meet recommendations for the food groups 'Vegetables and fruit' (49.9%), 'Grain products' (54.4%) and 'Meat and alternatives' (73.7%). Children adequately met nutrient requirements with the exception of calcium and fibre, of which intakes were low, and dietary fat and sodium, of which intakes were high. Skipping meals and purchasing meals at school or fast-food restaurants were statistically significant determinants of poor diet. Parents' assessment of their own eating habits was positively associated with the quality of their children's diets.

INTERPRETATION

Dietary intake among children in Nova Scotia is relatively poor. Explicit public health policies and prevention initiatives targeting children, their parents and schools may improve diet quality and prevent obesity.

Chronic disorders of the Achilles tendon: results of conservative and surgical treatments

We reviewed our results of nonoperative and operative treatment of chronic Achilles tenosynovitis to further define outcomes and treatment parameters. Forty-one patients presented with an average of 14 weeks of Achilles tendon symptoms. All patients received nonsurgical treatment initially, and 21 patients (51%) recovered after an average of 18 weeks of therapy. Three additional patients improved after brisement of the tendon/peritenon interspace. Seventeen of 41 patients eventually underwent soft tissue tenolysis and/or excision of degenerative tendon cysts. Those patients who responded to nonoperative therapy tended to be younger (average age, 33 years) than those who had degenerative tendon changes requiring surgery (average age, 48 years). All surgical patients were able to return to unrestricted activity after 31 weeks (range, 27-48 weeks). We believe 4 to 6 months of nonsurgical therapy is appropriate for middle aged patients or athletes with chronic Achilles tenosynovitis. Those that fail this treatment will improve with a limited debridement of diseased tissue without excessive soft tissue dissection of the tendon.

HIV-1 subtype C reverse transcriptase and protease genotypes in Zimbabwean patients failing antiretroviral therapy

HIV-1 drug resistance mutations have been identified and characterized mostly in subtype B HIV-1 infection. The extent to which antiretroviral drugs select for drug resistance mutations in non-subtype B HIV-1 is not known. We obtained HIV-1 reverse transcriptase (RT) and protease sequences from 21 Zimbabwean patients failing antiretroviral drug therapy. We compared these sequences with 56 published RT and protease subtype C sequences from untreated patients, 990 RT and 1140 protease subtype B sequences from treated patients, and 340 RT and 907 protease subtype B sequences from untreated patients and identified four mutation categories of subtype C HIV-1. Seventeen of the 21 patients (81%) had known drug resistance mutations. Mutations at 15 RT and 11 protease positions were more common in subtype C isolates than in subtype B isolates. HIV-1 subtype C-infected individuals receiving antiretroviral therapy develop many of the known subtype B drug resistance mutations. Comparison of subtype C RT and protease sequences with a large database of subtype B sequences identified subtype C-specific polymorphisms and candidate drug resistance mutations.

Power of exclusion for parentage verification and probability of match for identity in American kennel club breeds using 17 canine microsatellite markers

DNA analysis of microsatellite markers has become a common tool for verifying parentage in breed registries and identifying individual animals that are linked to a database or owner. Panels of markers have been developed in canines, but their utility across and within a wide range of breeds has not been reported. The American Kennel Club (AKC) authorized a study to determine the power to exclude non-parents and identify individuals using DNA genotypes of 17 microsatellite markers in two panels. Cheek swab samples were voluntarily collected at Parent Breed Club National Specialty dog shows and 9561 samples representing 108 breeds were collected, averaging 88.5 dogs per breed. The primary panel of 10 markers exceeded 99% power of exclusion for canine parentage verification of 61% of the breeds. In combination with the secondary panel of seven markers, 100% of the tested breeds exceeded 99% power of exclusion. The minimum probability match rate of the first panel was 3.6 x 10(-5) averaged across breeds, and with the addition of the second panel, the probability match rate was 3.2 x 10(-8); thus the probability of another random, unrelated dog with the same genotype is very low. The results of this analysis indicated that, on average, the primary panel meets the AKC's needs for routine parentage testing, but that a combination of 10-15 genetic markers from the two panels could yield a universal canine panel with enhanced processing efficiency, reliability and informativeness.

Breast-milk shedding of drug-resistant HIV-1 subtype C in women exposed to single-dose nevirapine

Single-dose nevirapine reduces intrapartum human immunodeficiency virus 1 type (HIV-1) transmission but may also select for nonnucleoside reverse-transcriptase inhibitor (NNRTI) resistance in breast milk (BM) and plasma. Among 32 Zimbabwean women, median 8-week postpartum plasma and BM HIV-1 RNA levels were 4.57 and 2.13 log(10) copies/mL, respectively. BM samples from women with laboratory-diagnosed mastitis (defined as elevated BM Na(+) levels) were 5.4-fold more likely to have HIV-1 RNA levels above the median. BM RT sequences were not obtained for 12 women with BM HIV-1 RNA levels below the lower limit of detection of the assay used. In 20 paired BM and plasma samples, 65% of BM and 50% of plasma RT sequences had NNRTI-resistance mutations, with divergent mutation patterns.

Intratumoural evolutionary landscape of high-risk prostate cancer: the PROGENY study of genomic and immune parameters

BACKGROUND

Intratumoural heterogeneity (ITH) is well recognised in prostate cancer (PC), but its role in high-risk disease is uncertain. A prospective, single-arm, translational study using targeted multiregion prostate biopsies was carried out to study genomic and T-cell ITH in clinically high-risk PC aiming to identify drivers and potential therapeutic strategies.

PATIENTS AND METHODS

Forty-nine men with elevated prostate-specific antigen and multiparametric-magnetic resonance imaging detected PC underwent image-guided multiregion transperineal biopsy. Seventy-nine tumour regions from 25 patients with PC underwent sequencing, analysis of mutations, copy number and neoepitopes combined with tumour infiltrating T-cell subset quantification.

RESULTS

We demonstrated extensive somatic nucleotide variation and somatic copy number alteration heterogeneity in high-risk PC. Overall, the mutational burden was low (0.93/Megabase), but two patients had hypermutation, with loss of mismatch repair (MMR) proteins, MSH2 and MSH6. Somatic copy number alteration burden was higher in patients with metastatic hormone-naive PC (mHNPC) than in those with high-risk localised PC (hrlPC), independent of Gleason grade. Mutations were rarely ubiquitous and mutational frequencies were similar for mHNPC and hrlPC patients. Enrichment of focal 3q26.2 and 3q21.3, regions containing putative metastasis drivers, was seen in mHNPC patients. We found evidence of parallel evolution with three separate clones containing activating mutations of β-catenin in a single patient. We demonstrated extensive intratumoural and intertumoural T-cell heterogeneity and high inflammatory infiltrate in the MMR-deficient (MMRD) patients and the patient with parallel evolution of β-catenin. Analysis of all patients with activating Wnt/β-catenin mutations demonstrated a low CD8+/FOXP3+ ratio, a potential surrogate marker of immune evasion.

CONCLUSIONS

The PROGENY (PROstate cancer GENomic heterogeneitY) study provides a diagnostic platform suitable for studying tumour ITH. Genetic aberrations in clinically high-risk PC are associated with altered patterns of immune infiltrate in tumours. Activating mutations of Wnt/β-catenin signalling pathway or MMRD could be considered as potential biomarkers for immunomodulation therapies.

CLINICAL TRIALS.GOV IDENTIFIER

NCT02022371.

Workplace surveillance for carpal tunnel syndrome using hand diagrams

Four hundred and eleven workers from 4 different companies participated in a worksite screening program designed, in part, to estimate the prevalence of carpal tunnel syndrome (CTS). Each worker completed a discomfort survey and underwent limited nerve conduction testing of the median and ulnar sensory nerves in both wrists. The discomfort survey included a hand diagram which allowed subjects to shade in area(s) affected by numbness, burning, tingling, or pain. The discomfort survey also asked each worker to indicate whether she or he had experienced neuropathic symptoms (i.e., numbness, burning, tingling, or pain) in the wrist, hand or fingers of each hand, without regard to localization (i.e., median versus ulnar versus radial distribution), and also nocturnal occurrence of symptoms. Analyses involved comparing hand diagram scores and non localized wrist/hand/finger symptoms with electrodiagnostic test results. All configurations of hand diagram scores of the dominant hands had a statistically significant association with electrophysiologically determined median nerve dysfunction, but so did non localized symptom reports. The sensitivity, specificity, and positive predicted values of hand diagrams were poorer than those reported previously. While some test performance characteristics of hand diagrams were better than those for non localized distal extremity symptoms consistent with CTS, some were worse. Overall, our data suggest that hand diagrams are no better than using a questionnaire to determine if workers have experienced symptoms consistent with CTS in their wrists, hands or fingers without regard to localization. The choice of screening tool would depend on the goal of screening, in particular, whether it is more desirable to have slightly higher sensitivity or positive predictive value.

Workplace surveillance for carpal tunnel syndrome: A comparison of methods

A variety of screening procedures for carpal tunnel syndrome (CTS) were applied among workers in a manufacturing plant, and results were compared. The test procedures included a symptom survey, physical examination, limited electrodiagnostic testing at the wrists, quantitative vibratory threshold testing, 2-point discrimination, palmar pinch grip, and hand grip strength testing. When electrodiagnostic testing alone was used as "gold standard," the sensitivity and positive predictive value (PPV) of physical examination findings and quantitative test procedures were no better than, and usually worse than, the results on the symptom survey alone. Variation of the constellation of symptoms (i.e., numbness, tingling, pain or burning) and the anatomic distribution of reported symptoms (i.e., fingers, hand, wrist, or forearm) for inclusion in the screening symptom definition of CTS yielded modest changes in the sensitivity and PPV of the symptom survey. However, addition of the requirement for nocturnal symptoms as part of the screening symptom definition for CTS resulted in substantially higher PPV with only slight reduction in sensitivity. These results suggest that, in the absence of electrodiagnostic testing, the simplest test, and the procedure with the highest sensitivity and PPV for CTS is a symptom survey alone. Quantitative test procedures (vibrometry, pinch grip strength, hand grip strength) and physical examination for findings consistent with CTS (e.g., Phalen's test, Tinel's test, thenar muscle wasting, 2-point discrimination) appear to contribute little, if any, additional information when screening subjects in the work setting.

High dose rate endobronchial brachytherapy in the management of primary and recurrent bronchogenic malignancies

BACKGROUND

The clinical, radiographic, and bronchoscopic records of patients treated with out-patient high dose rate (HDR) endobronchial brachytherapy were reviewed to determine its effectiveness in patients with malignant airway obstruction (with or without prior external beam radiation). In addition, quality of life and acute and chronic morbidity were evaluated.

METHODS

From January 1, 1989 to June 30, 1993, 46 patients received 128 HDR endobronchial treatments employing a high activity Ir-192 source with a remote afterloader. Patients treated had a total of 22 primary and 17 recurrent bronchogenic carcinomas, 7 of which were metastatic nonpulmonary tumors. Three separate fractions of 7.0 Gy were prescribed to a depth of 1.0 cm. and given 1 week apart. Twelve patients (30%) received prior external beam irradiation (median dose, 58 Gy).

RESULTS

Median follow-up for the entire group was 5 months (17.5 for surviving patients). Of the eight asymptomatic patients, five (62%) remained asymptomatic for the remainder of their lives. Of the 38 symptomatic patients, 28 (74%) had significant clinical improvement, and 12 of them remained improved for the duration of their lives. Of thirty-six (78%) patients examined for radiographic response, 25 (69%) had a partial or complete response to this treatment. In patients without prior irradiation, there was a tendency for a higher percentage of clinical and radiographic response. Two patients (4%) experienced mild, transient dysphagia, four patients developed self-limited radiation pneumonitis (9%), and three patients (7%) suffered fatal hemoptysis (all of these patients received prior or concurrent external beam radiotherapy). No factor (i.e., prior radiation therapy, number of catheters placed, surgery, or chemotherapy) predicted an increased risk of complications (P = NS).

CONCLUSIONS

Outpatient HDR endobronchial brachytherapy is effective in both preventing and relieving endobronchial obstruction in patients with or without prior irradiation, recurrent lesions, or metastatic nonpulmonary disease. A significant proportion of patients can be rendered asymptomatic for the duration of their lives, hence were provided with improved quality of life. These treatments are well tolerated and safe, and result in minimal long term morbidity.

Recapitulating human cardio-pulmonary co-development using simultaneous multilineage differentiation of pluripotent stem cells

The extensive crosstalk between the developing heart and lung is critical to their proper morphogenesis and maturation. However, there remains a lack of models that investigate the critical cardio-pulmonary mutual interaction during human embryogenesis. Here, we reported a novel stepwise strategy for directing the simultaneous induction of both mesoderm-derived cardiac and endoderm-derived lung epithelial lineages within a single differentiation of human-induced pluripotent stem cells (hiPSCs) via temporal specific tuning of WNT and nodal signaling in the absence of exogenous growth factors. Using 3D suspension culture, we established concentric cardio-pulmonary micro-Tissues (μTs), and expedited alveolar maturation in the presence of cardiac accompaniment. Upon withdrawal of WNT agonist, the cardiac and pulmonary components within each dual-lineage μT effectively segregated from each other with concurrent initiation of cardiac contraction. We expect that our multilineage differentiation model will offer an experimentally tractable system for investigating human cardio-pulmonary interaction and tissue boundary formation during embryogenesis.

Organs begin developing during the first few months of pregnancy, while the baby is still an embryo. These early stages of development are known as embryogenesis – a tightly organized process, during which the embryo forms different layers of stem cells. These cells can be activated to turn into a particular type of cell, such as a heart or a lung cell.

The heart and lungs develop from different layers within the embryo, which must communicate with each other for the organs to form correctly. For example, chemical signals can be released from and travel between layers of the embryo, activating processes inside cells located in the different areas.

In mouse models, chemical signals and cells travel between developing heart and lung, which helps both organs to form into the correct structure. But it is unclear how well the observations from mouse models translate to heart and lung development in humans.

To find out more, Ng et al. developed a human model of heart and lung co-development during embryogenesis using human pluripotent stem cells. The laboratory-grown stem cells were treated with chemical signals, causing them to form different layers that developed into early forms of heart and lung cells.

The cells were then transferred into a specific growing condition, where they arranged into three-dimensional structures termed microtissues. Ng et al. found that lung cells developed faster when grown in microtissues with accompanying developing heart cells compared to microtissues containing only developing lung cells. In addition, Ng et al. revealed that the co-developing heart and lung tissues automatically separate from each other during later stage, without the need for chemical signals.

This human cell-based model of early forms of co-developing heart and lung cells may help provide researchers with new strategies to probe the underlying mechanisms of human heart and lung interaction during embryogenesis.

A spectroscopic investigation of losartan polymorphs

Losartan, an antihypertensive agent in clinical development, was found to exist in two enantiotropic polymorphic forms, a low-temperature stable form (Form I) and a high-temperature stable form (Form II), the temperatures at which they are stable being related to the transition temperature. X-ray powder diffraction patterns indicated differences in the crystal packing of the two forms. The vibrational data from infrared and Raman spectroscopy suggested a subtle change in molecular conformation and crystal packing in the two forms. Solid-state 13C NMR data of the polymorphs concurred with the vibrational data and indicated that, while the observed line widths reflect no major changes in crystallinity, signal multiplicities and chemical shifts do reflect differences in molecular packing in the respective unit cells. Thus, in the absence of crystallographic data, useful structural information could be derived from spectroscopic results to identify each of the crystalline forms.

Labor and skills gap analysis of the biomedical research workforce

The United States has experienced an unsustainable increase of the biomedical research workforce over the past 3 decades. This expansion has led to a myriad of consequences, including an imbalance in the number of researchers and available tenure-track faculty positions, extended postdoctoral training periods, increasing age of investigators at first U.S. National Institutes of Health R01 grant, and exodus of talented individuals seeking careers beyond traditional academe. Without accurate data on the biomedical research labor market, challenges will remain in resolving these problems and in advising trainees of viable career options and the skills necessary to be productive in their careers. We analyzed workforce trends, integrating both traditional labor market information and real-time job data. We generated a profile of the current biomedical research workforce, performed labor gap analyses of occupations in the workforce at regional and national levels, and assessed skill transferability between core and complementary occupations. We conclude that although supply into the workforce and the number of job postings for occupations within that workforce have grown over the past decade, supply continues to outstrip demand. Moreover, we identify practical skill sets from real-time job postings to optimally equip trainees for an array of careers to effectively meet future workforce demand.-Mason, J. L., Johnston, E., Berndt, S., Segal, K., Lei, M., Wiest, J. S. Labor and skills gap analysis of the biomedical research workforce.

Quantitative vibrometry and electrophysiological assessment in screening for carpal tunnel syndrome among industrial workers: a comparison

Vibrometry has been demonstrated to be an effective adjunct to electrophysiological evaluation of nerve integrity in diffuse peripheral neuropathies but there is controversy over its value in the diagnosis of isolated compression neuropathy such as carpal tunnel syndrome (CTS). One hundred thirty factory workers were screened for peripheral nerve impairment using both vibrometry and electrophysiologic testing of digits 2 and 5 in both hands. Vibrometry had a low sensitivity in identifying individuals with symptoms of CTS or a median mononeuropathy defined by nerve conduction studies (NCS). The correlation of vibratory and the sensory evoked latencies were modest in the median nerve distribution (r = 0.297 to 0.370, p = 0.001). Using a comparison between vibration thresholds from digit 2 to 5 was not helpful in identifying cases of CTS and the difference in thresholds did not correlate with the difference in sensory evoked latencies. CTS is primarily a demyelinating process and can be easily detected with NCS. Because vibration threshold sensation is related to axonal loss it is not as sensitive in early CTS. Our results do not support the use of quantitative vibrometry as a screening tool median nerve impairment among industrial workers.

Infratentorial subdural empyema: clinical and computerized tomography findings. Report of three cases

Infratentorial subdural empyemas are rare. The authors report three cases encountered between 1979 and 1988, representing a 3% incidence among all subdural empyemas. The common source was an ear infection. Clinical presentation encompassed a systemic febrile illness, headaches, and a stiff neck. Only one patient had an inconspicuous focal neurological deficit that suggested a cerebral location. Initial diagnosis was acute meningitis in each case. A lumbar puncture was ordered in all three cases but was actually performed in two without developing tonsillar herniation. Cerebrospinal fluid analysis confirmed the diagnosis of meningitis in one but was normal in the other. Computerized tomography allowed a precise diagnosis and localization of the pathology. All three patients received aggressive antibiotic therapy plus suboccipital craniectomy and aspiration of pus; catheter drainage was performed in two. Cultures were positive in one case and negative in the others. Two patients were cured without sequelae; the third patient was moribund at surgery and died. Although it is known that subdural empyemas may localize in the posterior fossa, only one previous report was found. Infratentorial subdural empyema may sometimes be an unrecognized companion of acute meningitis and is cured with antibiotic therapy alone.

Drug resistance in plasma and breast milk after single-dose nevirapine in subtype C HIV type 1: population and clonal sequence analysis

Single-dose nevirapine (SD NVP) reduces intrapartum HIV-1 transmission, but nonnucleoside reverse transcription (NNRTI) resistance mutations can emerge. Population sequencing among 32 subtype C HIV-1-infected, SD NVP-exposed Zimbawean women demonstrated NNRTI resistance in 25/32 (78%) women: 23/30 (77%) at 2 weeks, 11/31 (35%) at 8 weeks, and 5/27 (19%) at 24 weeks. A total of 447 unique TA clones (median = 28 per time point), from four women with resistance at 8 weeks but wild-type virus by population sequence at 24 weeks, identified NNRTI mutations in a median of 76% (range: 55-96%) of individual clones at 2 weeks, 48% (range: 33-80%) at 8 weeks, and 5% (range: 0-15%) by 24 weeks. NNRTI mutations in breast milk clones at 2 and weeks from one woman varied significantly from plasma. Population sequencing underestimates the diversity of NNRTI resistance mutations within minority populations following SD NVP in subtype C HIV-1 viral RNA in plasma and breast milk.

Adipose Tissue Paracrine-, Autocrine-, and Matrix-Dependent Signaling during the Development and Progression of Obesity

Obesity is an ever-increasing phenomenon, with 42% of Americans being considered obese (BMI ≥ 30) and 9.2% being considered morbidly obese (BMI ≥ 40) as of 2016. With obesity being characterized by an abundance of adipose tissue expansion, abnormal tissue remodeling is a typical consequence. Importantly, this pathological tissue expansion is associated with many alterations in the cellular populations and phenotypes within the tissue, lending to cellular, paracrine, mechanical, and metabolic alterations that have local and systemic effects, including diabetes and cardiovascular disease. In particular, vascular dynamics shift during the progression of obesity, providing signaling cues that drive metabolic dysfunction. In this review, paracrine-, autocrine-, and matrix-dependent signaling between adipocytes and endothelial cells is discussed in the context of the development and progression of obesity and its consequential diseases, including adipose fibrosis, diabetes, and cardiovascular disease.