Enhanced self-renewal of human pluripotent stem cells by simulated microgravity

A systematic study on the biological effects of simulated microgravity (sµg) on human pluripotent stem cells (hPSC) is still lacking. Here, we used a fast-rotating 2-D clinostat to investigate the sµg effect on proliferation, self-renewal, and cell cycle regulation of hPSCs. We observed significant upregulation of protein translation of pluripotent transcription factors in hPSC cultured in sµg compared to cells cultured in 1g conditions. In addition to a significant increase in expression of telomere elongation genes. Differentiation experiments showed that hPSC cultured in sµg condition were less susceptible to differentiation compared to cells in 1g conditions. These results suggest that sµg enhances hPSC self-renewal. Our study revealed that sµg enhanced the cell proliferation of hPSCs by regulating the expression of cell cycle-associated kinases. RNA-seq analysis indicated that in sµg condition the expression of differentiation and development pathways are downregulated, while multiple components of the ubiquitin proteasome system are upregulated, contributing to an enhanced self-renewal of hPSCs. These effects of sµg were not replicated in human fibroblasts. Taken together, our results highlight pathways and mechanisms in hPSCs vulnerable to microgravity that imposes significant impacts on human health and performance, physiology, and cellular and molecular processes.

The "double discourse" on sexual and reproductive rights in Latin America: the chasm between public policy and private actions

This article examines how political controversies affect citizens' ability to exercise sexual and reproductive rights in Latin America. The article argues that societies accommodate conflicting views on sexuality and reproduction with a "double discourse system," which defends repressive or negligent public policies while privately tolerating unofficial and often illegal mechanisms that expand private sexual and reproductive choices. The examples of divorce policy in Chile and abortion policy in Colombia and Chile are highlighted to illustrate how this breach between public discourse and private actions operates in practice, and who is harmed by it. The article concludes by discussing the implications of this system for rights advocacy.

Liver transplantation for hepatitis B cirrhosis: clinical sequela of passive immunization

Aggressive administration of hepatitis B immune globulin (HBIg) has been shown to prevent hepatitis B viral (HBV) infection of the allograft; however, the clinical sequela of such therapy has not been previously described. We reviewed our experience with high dose, intravenous infusion of an intramuscular HBIg preparation to assess the effectiveness and complications of such therapy. Thirty three orthotopic liver transplants (OLTx) were performed in 32 patients with chronic HBV cirrhosis at the University of Virginia between March 1990 and June 1995. Twenty-nine of 32 (91%) patients remain free of HBV recurrence (defined by undetectable serum HBsAg and HBV-DNA) after a mean of 21 months (2-54 months), with one patient requiring retransplantation. Three (10%) patients died of non-HBV causes (two vascular events, one infectious event). Twenty episodes of acute cellular rejection were treated in 18 patients (two had two episodes). Sixteen rejections occurred within 18 d of transplant, 19 by day 120, and one late rejection occurred at 18 months owing to medication non-compliance. Eighteen patients had at least one documented infection. Six patients were treated for CMV infection (five empirically). Eight patients were treated for HSV infections (seven mild herpetic labialis and one herpetic keratitis). Four patients had documented fungal infection (one mucormycosis pneumonia and three minor superficial mucosal infections). With the exception of one necrotizing pneumonia, 11 bacterial infections were successfully treated with conventional antimicrobial agents. No patient developed post-transplant lymphoproliferative disorder. Symptoms associated with HBIg infusion were intermittent but frequent and consisted of myalgias, predominantly back pain (90%), headache (20%) and flushing (5%). No patient experienced anaphylaxis, fever, rash, arthritis or hypotension. Despite the potential for mercury toxicity and HCV transmission in the HBIg formulations currently available in the United States, serum mercury levels remained below standards for industrial exposure (60 micrograms/ml), and only one individual developed post-transplant HCV infection after receiving multiple units of unscreened blood prior to 1991.

SUMMARY

High-dose HBIg prevented HBV infection of the allograft in 29 of 32 patients transplanted for HBV cirrhosis with three non-HBV associated deaths. The intravenous infusion of HBIg was frequently associated with minor side effects that were safely tolerated by patients. The risk of HCV transmission and mercury toxicity are minimal, but support the need for a new intravenous formulation of HBIg. HBIg therapy successfully decreased post-OLTx HBV recurrence with no clinical events associated with immunosuppression. Patients did non experience allergic or infusion-related complications that altered or terminated therapy. Manufacturing modifications of HBIg may allow for improved patient tolerance and decreased risks.

Lung-specific direct in vivo gene transfer with recombinant plasmid DNA

A number of gene delivery methods have been developed to facilitate gene transfer into mammalian somatic cells in vivo. In this study, we demonstrated that tracheal insufflation of two recombinant plasmids containing a bacterial gene, chloramphenicol acetyltransferase (CAT), driven by the cytomegalovirus (CMV) immediate early promoter/enhancer, either alone or complexed to cationic liposomes, resulted in efficient and selective transfection of the lungs in rats. When the simian virus 40 (SV40) promoter/enhancer was used, there was no detectable transfection. Insufflation of plasmid DNA was as efficient as plasmid-liposome complexes in transfecting the lungs. Expression of the CAT gene in the lungs was noted as early as 1 day after insufflation of plasmid DNA alone or plasmid-liposome complexes, and lasted for > 21 days. In contrast, intravenous injection of plasmid alone or plasmid-liposome complexes did not result in transfection of the lungs. Because of its simplicity, without the potential adverse effect of any gene delivery systems, intratracheal delivery of recombinant plasmid DNA may have potential implication for lung-specific gene therapy.

Type A behavior pattern and emotion expression in younger and older adults

Eighty younger (less than 50 years, M = 28 years) and 80 older (more than 50 years, M = 69 years) Type A and Type B Ss were evaluated for Type A behavior pattern using the Structured Interview (SI) and given personality tests for anxiety, depression, anger, aggression, hostility, and anger-in-anger-out. Ss also underwent an emotion induction procedure. Videotapes of the emotion induction procedure (N = 160) and the SI (N = 80) were coded for facial expression of emotion. Type As did not differ from Bs on anxiety or depression but did on anger and aggression. Type As showed anger inhibition and anger bound to shame, as predicted by emotion socialization theory. The greatest number of differential effects were observed between age groups. Older individuals, in general, were more emotionally expressive than younger Ss across a range of emotions. Women appeared more conflicted about anger expression than men, and Type A women more so than Type A men.

Type A behavior pattern and emotion expression in younger and older adults

Eighty younger (less than 50 years, M = 28 years) and 80 older (more than 50 years, M = 69 years) Type A and Type B Ss were evaluated for Type A behavior pattern using the Structured Interview (SI) and given personality tests for anxiety, depression, anger, aggression, hostility, and anger-in-anger-out. Ss also underwent an emotion induction procedure. Videotapes of the emotion induction procedure (N = 160) and the SI (N = 80) were coded for facial expression of emotion. Type As did not differ from Bs on anxiety or depression but did on anger and aggression. Type As showed anger inhibition and anger bound to shame, as predicted by emotion socialization theory. The greatest number of differential effects were observed between age groups. Older individuals, in general, were more emotionally expressive than younger Ss across a range of emotions. Women appeared more conflicted about anger expression than men, and Type A women more so than Type A men.

Phase II study of fluorouracil and recombinant interferon alfa-2a in previously untreated advanced colorectal carcinoma

We conducted a phase II clinical trial of fluorouracil (5FU) and recombinant interferon alfa-2a (rIFN alpha-2a) in 52 previously untreated patients with bidimensionally measurable metastatic colorectal cancer. During week 1, 5FU was administered as a continuous intravenous infusion, 750 mg/m2/d for 5 consecutive days. Intravenous bolus administration of 5FU 750 mg/m2 was given weekly for 7 weeks starting on day 12. rIFN alpha-2a (Roferon; Hoffman-LaRoche, Nutley, NJ), 9 x 10(6) U, was administered subcutaneously three times weekly during weeks 1 to 8. Patients were evaluated for response on week 9. Of 52 patients enrolled in the study, 51 were assessable for toxicity, and 45 were assessable for response. Fifteen patients experienced partial response, and one patient achieved a clinical complete response for an overall response rate of 35% (95% confidence interval [CI], 22%, 50%). Median duration of response is 7.5 months (range, 4 to 11 months). Seventy percent of patients entered on the study are alive with a median follow-up duration of 7 months. Twenty-five percent of patients developed grade 4 toxicity, and 82% developed grade 3 toxicity. One drug-related death in the presence of sepsis was reported, and two treatment-related seizures occurred. Our experience with this schedule produced a lower response rate with greater toxicity than previously reported. Current randomized trials comparing this schedule of 5FU with rIFN alpha-2a to 5FU plus folinic acid (leucovorin) or single-agent 5FU may determine its role in the treatment of advanced colorectal carcinomas.

An electron microscopic study of local anesthetic-induced skeletal muscle fiber degeneration and regeneration in the monkey

An electron microscopic study was done on abductor pollicis brevis muscles of 18 Rhesus monkeys after intramuscular injections of 0.75% bupivacaine, 2% mepivacaine, or 2% lidocaine + epinephrine. The muscles were examined for from 2 h to 28 days. Severe muscle fiber damage, consisting of breakdown of sarcolemma and myofibrils, was seen as early as 2 h. Phagocyte mediated fragmentation of the degenerating muscle fibers was at its peak during the third and fourth days. Myoblasts were abundant during the fourth day. Early myotubes appeared on the fifth and sixth days, and they matured during the second week. Satellite cells appeared alongside mature myotubes. Overall, the local anesthetic-induced breakdown and regeneration of skeletal muscle fibers in the monkey followed a course quite similar to that seen in the rat.

A histological study of local anesthetic-induced muscle degeneration and regeneration in the monkey

Small amounts (1-2 ml) of local anesthetics (bupivacaine, lidocaine, and mepivacaine) were injected into the abductor pollicis brevis muscles of 35 monkeys. Control muscles were injected with saline. The muscles were preserved for histology from 4.5 h to 48 days after the injection. Histological damage to muscle fibers was evident from the time of the first sampling. Invasion of damaged muscle fibers by phagocytic cells was prominent by 2-3 days postinjection. At 4 to 5 days, areas of muscle fiber damage were characterized by dense concentrations of phagocytes and mononuclear myoblastic cells. At 6 days, fields of early myotubes were evident. Maturation of myotubes into immature cross-striated muscle fibers occurred over the next week. Occasional myotubes or immature regenerating muscle fibers were seen as late as 28 days. The topographical pattern of muscle fiber degeneration and regeneration showed a concentration along the surfaces of muscle fascicles or, if intrafascicular, around the presumed site of injection.

Soft tissue sarcoma and military service in Vietnam: a case-control study

A case-control study was conducted in men who were of draftable age during the Vietnam conflict to examine the association of soft tissue sarcomas (STSs) with military service in Vietnam as well as other host and environmental risk factors. A total of 217 STS cases selected from the Armed Forces Institute of Pathology were compared to 599 controls for Vietnam service, occupational and nonoccupational exposure to various chemicals, occupational history, medical history, and life-style (smoking, alcohol, coffee, etc.). Military service information was verified by a review of the patient's military personnel records. Other information was ascertained from a telephone interview with either subjects or their next of kin. Cases and controls were stratified on the basis of the hospital type (civilian, Veterans Administration, and military); the Mantel-Haenszel estimate of the odds ratio (OR), adjusted for the effects of the stratification variable, was calculated. Vietnam veterans in general did not have an increased risk of STS when compared to those men who had never been in Vietnam (OR, 0.85; 95% confidence interval, 0.54-1.36). Subgroups of Vietnam veterans who had higher estimated opportunities for Agent Orange exposure seemed to be at greater risk of STSs when their counterparts in Vietnam were taken as a reference group. However, this risk was not statistically significant.

Transient expression system to measure the efficiency of vaccinia promoter regions

A transient expression system has been developed to compare the relative efficiency of expression of various vaccinia virus DNA sequences containing transcriptional regulatory elements. A plasmid vector was constructed containing both the Escherichia coli galactokinase gene (galK) and the guanine phosphoribosyltransferase gene (gpt). To direct the expression of gpt within this vector, a vaccinia virus promoter region was isolated from the HindIII-F fragment of the genome and inserted 5' to gpt coding sequence. Four unique cloning sites in front of galK allow simple and precise fusion of various vaccinia virus DNA fragments that contain the regulatory site of interest to galK. Sequences containing promoter regions were ligated to the coding segment of the galK to create four recombinant plasmids, which were introduced into vaccinia virus-infected cells by transfection. Both galK and gpt were thus expressed under the control of vaccinia virus transcriptional units, and the enzymatic activities were measured in the same cell extract with a filter-binding assay. The major advantage of this transient expression system is that the variations in galK expression are always measured relative to the internal gpt standard. Changes in the galK/gpt ratio resulting from different vaccinia promoters of galK are thus a quantitative measurement of promoter strength.

Outpatient surgery in pediatric urology patient

Outpatient surgery in children with straightforward surgical problems has proved to be safe and cost effective. We have analyzed our experience in 138 consecutive "short-stay" surgical patients in terms of (1) cost effectiveness, (2) surgical procedure, and (3) complications. Selection of a patient for outpatient surgery requires a thorough preoperative evaluation as well as close cooperation between surgeon, anesthesiologist, and operating room staff.