Transversus abdominis plane blocks in laparoscopic inguinal hernia repair: a review

INTRODUCTION

Throughout its history, there have been significant advances in pain control of inguinal hernia repairs. One of the most recent developments is locoregional pain blocks. There is a multitude of literature available on laparoscopic inguinal hernia repair and transversus abdominis plane (TAP) blocks.

OBJECTIVES

This paper seeks to provide a thorough and systematic literature review on the role of TAP blocks in laparoscopic inguinal hernia repairs.

METHODS

PubMed and Google Scholar were searched for relevant literature using predetermined medical subject heading (MeSH) terms: "(TAP block)" AND "(Laparoscopic inguinal hernia repair)".

RESULTS

A total of 166 publications were identified, from which 18 publications were included in the final review after eligibility criteria were applied.

CONCLUSION

The majority of studies conclude that TAP blocks performed in the setting of laparoscopic inguinal hernia repair improve post-operative pain and mobility, decrease opiate analgesic usage, and are superior in pain control compared to other modalities of regional anesthesia. Thus, to improve post-operative outcomes and patient satisfaction, TAP blocks should be heavily considered for routine use in surgical practice for laparoscopic inguinal hernia repair.

Cancer awareness in Australian adolescents

BACKGROUND

Over one-third of cancer cases are attributable to modifiable risk factors. Because health-related behaviors are often established at adolescence, it is important that adolescents understand the risks and lifestyle decisions that may reduce their chances of developing cancer. This study aims to identify the levels of cancer awareness of adolescents in Australia.

METHODS

Paper questionnaires were used to collect information about baseline levels of cancer awareness. These questionnaires included socio-demographic questions and the Cancer Awareness Measure (CAM) with slight modifications to ensure their suitability for the Australian adolescent population. Students aged 11 to 19 years were recruited from 13 Australian high schools between 2016 and 2019.

RESULTS

A total of 766 adolescents (58% female, mean age = 14.5 years) completed the questionnaires. Adolescents' cancer awareness was low. Adolescents who knew someone with cancer recognized significantly more cancer risk factors and cancer warning signs than those who did not know someone with cancer (t (756) = 2.35, p = .019; t (747) = 5.57, p = .001). Those from high Index of Community Socio-Educational Advantage (ICSEA) schools significantly recognized more cancer risk factors than those from low ICSEA schools (t (764) = 2.42, p = .016). Females recognized significantly more warning signs than males (t (583) = 3.11, p = .002) and students from senior high school grades recognized more warning signs than those from junior grades (t (754) = 2.24, p = .02). Most adolescents (78%) were aware of skin cancer as one of the most common cancers in Australia, however half or less were aware of other common cancers. Although most adolescents would seek medical help in the presence of possible cancer symptoms as soon as possible, approximately 20% of them would not see a doctor promptly. Emotional barriers were the most common reasons to delay seeing a doctor (56%), for example "being worried about hearing bad news" (27%).

CONCLUSIONS

Australian adolescents show poor awareness of cancer risk factors and cancer warning signs. A number of demographic and experience factors were found to be related to lower cancer awareness. Education is essential to raise cancer awareness, promote healthy lifestyles from adolescence and avoid a preventable cancer diagnosis.

Pregnancy-driven cardiovascular maternal miR-29 plasticity in obesity

BACKGROUND

Obesity in pregnancy (MO) is a risk factor for maternal and/or fetal cardiovascular system disorders. This study evaluated maternal CVS expression of microRNA-29 family and its target molecules in MO to test the hypotheses: CVS miR-29 concentrations are increased in pregnancy and decreased in MO.

METHODS

Non-pregnant (n=4), pregnant obese (POb, n=4), and pregnant non-obese (PnOb, n=4) baboons (Papio spp.) were studied. Maternal left ventricle (LV), left atrium (LA), and aortic arch (AA) were collected at the end of gestation. Expression of MiR-29 and elastin (ELN) mRNA were quantified.

RESULTS

LA miR-29 (a, c) expression was highest in PnOb. In the LV, miR-29b expression trended lower (P=.059) for PnOb animals. ELN mRNA expression correlated positively with miR-29b expression in AA (r=.76, P=.03).

CONCLUSION

Maternal obesity diminishes miR-29 adaptation to pregnancy. Pharmacologic, tissue-specific targeting of miRNA-29 may represent a strategy for prevention and treatment of MO complications.

KIT-positive Gastrointestinal Stromal Tumor in a 22-year-old Male Chimpanzee (Pan troglodites)

Gastrointestinal stromal tumors (GIST), KIT-positive and KIT signaling driven or platelet-derived growth factor receptor α (PDGFRA) signaling driven mesenchymal tumors, are poorly known in nonhuman primates. Availability of KIT- and PDGFRA-inhibitor drug imatinib mesylate has greatly raised the interest for these tumors. At necropsy of a 22-year-old male chimpanzee, a round, firm 2-cm intramural tumor was incidentally found in the midbody of the stomach and diagnosed as a GIST. Histologically, the mass was composed of spindle to polygonal epithelioid cells arranged in short to intermediate-length, interlacing streams, bundles, and nodular whorls often separated by hyalinized eosinophilic matrix. The mitotic rate was a maximum 1/50 high-power field. Immunohistochemically, the tumor cells were diffusely positive for KIT and CD34, focally positive for α-smooth muscle actin, and negative for muscle specific actin, desmin, S-100 protein, synaptophy-sin, and glial fibrillary acidic protein. Because the majority of human GISTs have gain-of-function KIT or PDGFRA mutations, genomic sequences of KIT exons 9, 11, 13, and 17 and PDGFRA exons 12 and 18 from this chimpanzee GIST were polymerase chain reaction amplified and sequenced. However, no mutation was identified in the analyzed “mutational hot spots.” This study is the first extensive histomorphologic, immunohistochemical, and molecular genetic analysis of a chimpanzee GIST. More cases of nonhuman primate GISTs should be analyzed to discover the clinicopathologic spectrum of GISTs in these species.

Abruptio placentae in cynomolgus macaques (Macaca fascicularis): male bias

BACKGROUND

Abruptio placentae is a serious problem with a high rate of maternal and fetal mortality and documented sexual dimorphism in reoccurrence. Macaca fascicularis is a well-described reproductive model; however, there are no data available regarding sexual dimorphism in abruptio placentae in these species.

METHODS

A retrospective study of pathology and medical records in a large colony of M. fascicularis was performed. Placental specimens were analyzed.

RESULTS

The incidence of placenta abruptio in the colony was 15.7/1000 births. In the abruptio placentae group, male fetuses had lower placental disk length and increased femur length compared with female fetuses. The feto-pacental ratio and fetal weight were lower in the male fetuses in the abruption group compared with those in the stillbirth group without abruption placentae.

CONCLUSION

This is the first documentation of male bias in placental and fetal development in abruptio placentae in non-human primates.

Recurrent abruptio placentae in a cynomolgus monkey (Macaca fascicularis)

INTRODUCTION

Abruptio placentae, defined as premature separation of a normally implanted placenta, is a life threatening pregnancy complication with unknown pathophysiology. A history of abruptio placentae is the major risk factor for this pregnancy complication in humans. We describe the first case of recurrent abruptio placentae in a Macaca fascicularis.

MATERIAL AND METHODS

A pregnant M. fascicularis at term gestation was presented with weakness and hypothermia. Cesarean section revealed retroplacental hemorrhage with partial placental separation from the uterus.

RESULTS

The weight of the female fetus was within the lower birth weight range for these species. The maternal side of placenta contained necrotic tissue, occupying approximately 60% of the maternal surface. The placental implantation bed demonstrated neutrophil infiltration. Perivascular collections of lymphocytes were noticed in the uterine smooth muscle.

CONCLUSION

This case report underlines the importance of neutrophil infiltration and uterine venous drainage in the cascade of events leading to abruptio placentae.

Pleuro-pulmonary endometriosis in baboons (Papio spp.): insights into pathogenesis

BACKGROUND

Human pleuro-pulmonary endometriosis (PPE) is rare. Recently, we identified several cases of abdominal endometriosis in baboons that developed PPE.

MATERIALS AND METHODS

Ten cases of PPE and four of intra-abdominal endometriosis (three simultaneous) were identified at necropsy in baboons (Papio spp.) found dead due to natural causes. The endometriotic lesions were evaluated using immunohistochemistry.

RESULTS

The stromal (CD10+) and epithelial cells in intra-abdominal cases were estrogen and progesterone receptor (ER/PR) positive and thyroid transcription factor 1 (TTF-1) negative similar to that seen in humans. In contrast, the PPE cases displayed TTF-1-positive epithelium lining the cystic spaces, while the stroma was ER/PR positive similar to that in abdominal endometriosis. Both lymph nodes and spindle cell rests in lung interstitium contained ER/PR-positive stromal cells.

CONCLUSIONS

The lung lesions were different from the abdominal lesions in having a TTF-1-positive lining epithelium. The deep pulmonary interstitial and lymph node endometrial stromal rests probably arrive via lymphatic route. The endometrial stroma is the driving force in PPE upon which the lung-specific epithelium condenses and may require a novel approach to therapy.

Angle dependent optical properties of polymer films with a biomimetic anti-reflecting surface replicated from cylindrical and tapered nanoporous alumina

Anodic porous alumina nanostructures have been fabricated with tapered and cylindrical pores with a spacing of 100 and 200 nm and depth of 180-500 nm. The porous nanostructures were replicated into polymer films to create a moth-eye anti-reflecting surface by a roll-to-roll UV replication process. The angle dependent optical transmission of the resulting polymer films exhibited up to a 2% increase in transmission at a normal angle and up to a 5% increase in transmission at a 70° angle of incidence to an equivalent film with a surface replicated from polished aluminum. No significant difference was observed between the optical performance of moth-eye surfaces formed from cylindrical and tapered nano-pores.

Recognition by family members that relatives with neurodegenerative disease are likely to die within a year: a meta-ethnography

OBJECTIVE

To synthesize evidence of family members recognizing that their relative is likely to die within the year, and identifying the need for palliative care.

DESIGN

A meta-ethnography of studies of family members in multiple sclerosis (MS), Parkinson's disease (PD) and motor neuron disease (MND).

REVIEW METHODS

Systematic search in electronic databases; thematic synthesis guided by the principles of meta-ethnography, which is a method for thematic synthesis of qualitative studies.

RESULTS

Nine articles were included. The results of the synthesis identified two key themes. First, family members are intimately aware of changes in their relative's health and well-being. Sub-themes include family member awareness of different and progressive stages of the disease, noticing deterioration, noticing decline in functional abilities and recognizing that their relative will die. The second key theme is dilemmas of being involved in prognostication. Sub-themes include family member ambivalence toward hearing about prognostication, health professionals not being knowledgeable of the disease and family reluctance to receive palliative care.

CONCLUSIONS

Family members monitor and recognize changes in their relative with PD, MND and MS and in themselves. Thus, drawing on the expertise of family members may be a useful tool for prognostication.

Ductal Plate Malformation in a Nonhuman Primate

During necropsy of a 6-year-old, male African Green monkey ( Cercopithecus aethiops), multifocal pale, white to tan areas, 1–2 cm in diameter, were noted in the right lateral lobe, medial lobe, and capsular surface of the liver. Light microscopic examination of the liver revealed numerous spindle cells dispersed within interconnecting, broad bands of collagen, up to 200 μm in width, which often spanned and connected portal areas. A diagnosis of hepatic ductal plate malformation, most closely resembling congenital hepatic fibrosis with von Meyenburg complexes, was made. Few cases of ductal plate malformations in domestic animals are reported in the literature. To our knowledge, this is the first case reported in a nonhuman primate.

Involving people affected by cancer in research: a review of literature

The purpose of the literature review was to find out why people affected by cancer have been involved in research; how they have been involved and the impact of their involvement. We used systematic methods to search for literature, applied inclusion and exclusion criteria, conducted a quality appraisal, selected relevant data from the included articles for analysis, and provided a narrative summary of these data. The literature shows that people affected by cancer, particularly women with breast cancer, have been involved in a range of research programmes, projects and initiatives especially in the USA, UK, Canada and Australia. Their involvement has impacted upon research design, accrual and response rates. There is increasing recognition of the need for an infrastructure, including formal recruitment procedures, training and mentoring, to support an agenda of involvement and a need to challenge the ethos of traditional research, which does not easily lend itself to this agenda. Further critique of the role of 'experiential knowledge' in research is required so that researchers and people affected by cancer can work in partnership.

Adipokine expression is associated with adipocyte volume in baboons

Baboons show significant variation in body weight and composition, coupled with insulin resistance and phenotypes associated with the metabolic syndrome. An omental adipose tissue biopsy and a fasting blood sample were collected from 40 unrelated adult baboons from the colony at Southwest Foundation for Biomedical Research in San Antonio, TX. Serum was separated for analyses of circulating levels of glucose, insulin, adiponectin, resistin, interleukin 6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1 or CCL-2). Adipose tissue biopsies were analyzed for cell volume and number. Total RNA was isolated from adipose tissue and adiponectin, resistin, delta-resistin, MCP-1 and IL-6 mRNA abundance were measured using real time, quantitative RT-PCR. Partial correlation coefficients were calculated among adipokine expression, fat tissue cell volume, and circulating levels of proteins. Cell volume was significantly correlated with expression of MCP-1 (r=0.44, p<0.05) and IL-6 mRNA (r=0.47, p<0.01). A step wise regression analysis was conducted with adipose tissue cell volume as dependent variable. The model identified IL-6 mRNA levels in adipose tissue as the only predictor. These observations support the role of IL-6 as a possible paracrine regulator in adipose tissue.

The IGF axis in baboon pregnancy: placental and systemic responses to feeding 70% global ad libitum diet

Information on the influence of poor maternal nutrition on the regulation of responses to pregnancy, placental and fetal growth and development is critical to a better understanding of pregnancy physiology and pathophysiology. We determined normal changes and effects of controlled and monitored moderate nutrient restriction (NR) (global nutrient intake reduced to 70% of food consumed by mothers feeding ad libitum from 0.16 to 0.5 of gestation) in the baboon, on important hematological, biochemical, and hormonal indices of fetal growth and placental function. Serum IGF-I:IGFBP-3 ratio was lower in pregnant than control non-pregnant baboons feeding ad libitum. Serum concentrations of total and free IGF-I were decreased in NR mothers compared with controls (p<0.05). The decrease in fetal IGF-I did not reach significance (p=0.057). Serum IGF-I: IGFBP-3 ratio was decreased by NR in both mothers and fetuses. Maternal serum IGF-II was unchanged by NR. Placental IGF-I mRNA and protein abundance were similarly reduced whereas IGF-II mRNA increased in placental tissue of NR compared to control mothers. Systemic (maternal) and local (placental) IGFBP-1 and IGFBP-3 mRNA and protein abundance were unchanged by NR. Type 1 IGF receptor protein in the syncytiotrophoblast increased in NR. Type 2 IGF receptor protein was present in the stem villi core, and decreased after NR. We conclude that moderate NR in this important non-human primate model significantly disrupts the maternal and placental IGF-IGFBP axis and influences placental expression of this key system at the gene and protein level. Changes observed appear to be directed toward preserving placental growth.

Moderate maternal nutrient restriction, but not glucocorticoid administration, leads to placental morphological changes in the baboon (Papio sp.)

The aims of the present study were to describe the ontogeny of spatial relationships between placental components in baboons and to investigate alterations in these indices following (1) moderate maternal nutrient restriction and (2) administration of glucocorticoids to pregnant baboons. We investigated the effects of glucocorticoids since they have been shown to play a role in the altered fetal growth that accompanies maternal nutrient restriction. Glucocorticoids are also given to pregnant women who threaten premature labor to accelerate fetal lung maturation. A third aim was to compare our findings to those in similar conditions in human pregnancy. Volumetric placental development in the baboon was similar to that in the human, although growth of fetal capillaries was slower over the second half of gestation in baboon than in human placentas. Intervillous space (IVS) and villous star volumes were halved at the end of gestation compared to the middle of gestation, as described in the human placenta. When mothers were fed 70% of feed eaten by controls fed ad libitum, placental volumetric structure was unchanged at mid-gestation but was altered by the end of gestation when placental weight, but not fetal weight or length, was decreased. At the end of gestation villous volume and surface area, capillary surface area, and the villous isomorphic coefficient were all decreased, In contrast, IVS hydraulic diameter was increased. All parameters were similar in pregnancies with male and female fetuses, with the exception of fetal capillary volume, which was unchanged in pooled samples and those from male fetuses, but decreased in pregnancies with female fetuses. Glucocorticoid administration during the second half of gestation did not produce any changes in the measured indices of placental composition. In summary, these changes in placental structure, associated with maternal nutrient restriction, would all act to decrease placental transport of nutrients. The influence of MNR on villous capillarization depends on fetal gender.

Sparganosis in wild-caught baboons (Papio cynocephalus anubis)

BACKGROUND

Sparganosis is the infection of a paratenic host with the plerocercoid metacestode of Spirometra spp. A 12-year-old captive, pregnant, wild-caught baboon from Tanzania had multiple subcutaneous nodules.

METHODS

Examination of the biopsied nodules revealed the presence of viable metacestodes. The histological morphology of the metacestodes was consistent with the genus Spirometra and other pseudophyllidean cestodes. Since species of Spirometra produce growth hormones that are active in mammals, we measured fetal and placental growth and hormone levels. Blood samples were taken from the mother and the cesarean-derived fetus for hematological, biochemical, and hormonal analyses and to test for the presence of antispargana antibodies.

RESULTS

Baboon placental weight and fetal hematological, biochemical, and morphometric parameters were within normal ranges. Antibody titers to spargana did not differ significantly between mother (1.08 OD(405)) and fetus (0.91 OD(405)). Baboon maternal insulin-like growth factor and growth hormone values were also within the normal range. Estradiol and progesterone analysis in four of these animals (antibody titers ranged from 0.71 to 1.7 OD(405)) showed no statistically significant difference with age- or phase-matched cycle parameters compared with antibody-negative females.

CONCLUSIONS

Based on the results that have been obtained, sparganosis did not appear to affect the endocrinological profile of pregnant and cycling female baboons.

Including older people with dementia in research: challenges and strategies

This paper examines key challenges and strategies for including older people with dementia in an ethnographic study of quality of life in institutional care settings. The methods of interview and observation are described in relation to meeting four research challenges: verbal communication impairment, memory loss, decision-making capacity, and emotional disposition. A range of strategies for privileging the voice of the person with dementia is recommended which include: using different methods be spoke to each person with dementia; greater flexibility and time; preliminary meetings with the person with dementia; discussions with formal and informal carers; and research training. The researchers also conclude that the use of observation and interview are 'meaning-making occasions' which are qualitatively different but equally valuable for understanding quality of life in care settings.

Recombinant T cell receptor molecules can prevent and reverse experimental autoimmune encephalomyelitis: dose effects and involvement of both CD4 and CD8 T cells

Autoimmune diseases are often characterized by spontaneous remission followed by relapses. Although the mechanism(s) controlling pathogenic self-reactive T cells are not fully understood, recent data in experimental autoimmune encephalomyelitis (EAE), a prototype for CD4 T cell-mediated autoimmune diseases, indicate that spontaneous recovery is mediated by regulatory T cells (Treg) specific for peptides derived from the beta-chain of the TCR. Here we have tested whether recombinant single-chain TCRs (scTCRs) containing Vbeta domains can be used as vaccines for efficient priming of Treg. A single injection of mice with these recombinant proteins leads to efficient in vivo priming of Treg and almost complete protection from Ag-induced EAE. Significantly, administration of scTCRs during ongoing disease at a 10-fold lower dose than that required for prophylactic treatment also reverses established EAE. However, if a higher dose of scTCR is administered during ongoing disease, paralytic symptoms become exacerbated and the majority of treated animals die from severe and chronic EAE. Furthermore, we demonstrate that regulatory determinants are processed and presented from scTCRs resulting in the recruitment of both CD4 and CD8 regulatory T cells which are required for efficient regulation induced by scTCR. Reversal of established disease following an optimum dose of recombinant TCRs suggests that proteins expressing appropriate Vbeta domains could be used for the treatment of a variety of T cell-mediated pathologic conditions.

Recombinant T cell receptor molecules can prevent and reverse experimental autoimmune encephalomyelitis: dose effects and involvement of both CD4 and CD8 T cells

Autoimmune diseases are often characterized by spontaneous remission followed by relapses. Although the mechanism(s) controlling pathogenic self-reactive T cells are not fully understood, recent data in experimental autoimmune encephalomyelitis (EAE), a prototype for CD4 T cell-mediated autoimmune diseases, indicate that spontaneous recovery is mediated by regulatory T cells (Treg) specific for peptides derived from the beta-chain of the TCR. Here we have tested whether recombinant single-chain TCRs (scTCRs) containing Vbeta domains can be used as vaccines for efficient priming of Treg. A single injection of mice with these recombinant proteins leads to efficient in vivo priming of Treg and almost complete protection from Ag-induced EAE. Significantly, administration of scTCRs during ongoing disease at a 10-fold lower dose than that required for prophylactic treatment also reverses established EAE. However, if a higher dose of scTCR is administered during ongoing disease, paralytic symptoms become exacerbated and the majority of treated animals die from severe and chronic EAE. Furthermore, we demonstrate that regulatory determinants are processed and presented from scTCRs resulting in the recruitment of both CD4 and CD8 regulatory T cells which are required for efficient regulation induced by scTCR. Reversal of established disease following an optimum dose of recombinant TCRs suggests that proteins expressing appropriate Vbeta domains could be used for the treatment of a variety of T cell-mediated pathologic conditions.

Hyperplastic foveolar gastropathy and hyperplastic foveolar gastritis in baboons

While reviewing gastric specimens from 215 baboons, we found diffuse giant mucosal folds in 2 specimens and multiple giant mucosal nodules in another 3. The increased mucosal thickness in those areas was due to giant hyperplasia of the foveolar epithelium. The former 2 specimens were classified as Menetrier's disease (MD) and the latter 3 as Varioliform Lymphocytic Gastritis (VLG), since they were histologically identical to those gastropathies in humans. Whereas MD had diffuse giant hyperplastic foveoli (without lymphocytic infiltration) and prominent glandular cysts, VLG had nodules due to giant hyperplastic foveoli with intraepithelial lymphocytosis. Since the causes leading to gastric MD and VLG in humans remain unknown, the spontaneous occurrence of these two conditions in the baboon may open new avenues for the investigation of possible etiologic factors in the laboratory.

Total reconstruction of the temporomandibular joint with cryogenically preserved allograft mandibular condyle, meniscus, and fossa in the adult goat

OBJECTIVE

The purpose of this study was to determine the feasibility of total temporomandibular joint reconstruction with the use of cryogenically preserved allograft mandibular condyle, disk, and fossa in the adult goat.

STUDY DESIGN

This study consisted of an experimental group of 10 adult goats that underwent total resection of their temporomandibular joints. These animals were immediately reconstructed with cryogenically preserved mandibular condyles, disks, and fossa. These allograft were harvested from 10 donor animals matched to the recipient animal with respect to age, sex, and head dimensions. These grafts were harvested and stored at -185 degrees C for several months before implantation. At 2 years after surgery, the animals were killed. They were evaluated, clinically, radiographically, and histologically.

RESULTS

Fifty percent of the eight surviving animals had a normal clinically functional joint with an intact superior joint space and viable articular surfaces.

CONCLUSION

The authors conclude that this temporomandibular joint reconstruction technique is feasible in the adult goat model and is deserving of further research.

Infection of baboons with simian/human immunodeficiency viruses

Baboons were evaluated for their utility to serve as a model for testing envelope-based vaccines against human immunodeficiency virus type 1 (HIV-1). The ability of HIV-1 strains IIIB, RF, and SF2 to infect baboons was compared with that of simian/human immunodeficiency virus (SHIV) recombinant viruses comprised of either HXB2 or SF2 env, tat, rev, and vpu genes inserted into the SIVmac239 backbone. Both SHIV recombinants replicated in baboon PBMC in vitro, while no evidence of replication was noted for HIV-1 strains (MN, IIIB, SF2). Infection of baboons in vivo correlated with the restriction of infection in vitro. Virus was recovered by cocultivation methods early after SHIV (HXBc2) infection of two baboons with seroconversion profiles that parallel those observed in simian immunodeficiency virus (SIV)mac-infected rhesus monkeys. One of two baboons inoculated with SHIV(SF2) also seroconverted within 4 weeks; however, the kinetics of infection in a second animal appeared much later, with seroconversion to gp120 not evident until 20 weeks and no virus recovery during 32 weeks following infection. Viral DNA was detected in the lymph nodes of the SHIV-inoculated animals by nested polymerase chain reaction (PCR) amplification. Histopathologic changes were evident in lymph nodes, yet no overt clinical disease was observed. When HIV-1 strains (IIIB, RF, and SF2) were inoculated into baboons, virus was not recovered and no seroconversion to the major HIV-1 antigens was observed. However, viral DNA from the lymph nodes of four animals inoculated with HIV-1 strains could be detected by nested PCR, indicating a persistent but diminutive infection of HIV-1. The baboon thus represents a new animal model for testing HIV-1 envelope-based vaccines including the evaluation of new immunogens, dosages, routes, and adjuvants that act in eliciting protective responses.

A comparison of the form and function of the human, monkey, and goat temporomandibular joint

The anatomic form and function of the human temporomandibular joint is compared with the monkey (Macaca and Papio) and goat joint. The findings indicate that the joint of the goat seems to be superior to the joint of Macaca and Papio as a research model.

Purification and characterization of alpha 1-antichymotrypsin-like protease inhibitor that regulates prohormone thiol protease involved in enkephalin precursor processing

Evidence is presented showing that alpha 1-antichymotrypsin (ACT) inhibits a novel prohormone thiol protease (PTP) involved in processing the enkephalin precursor. Colocalization of ACT immunoreactivity with PTP within isolated secretory vesicles of bovine adrenal medulla and pituitary indicated that endogenous ACT could regulate PTP in vivo. The endogenous 60 kDa bovine ACT (bACT)-like protein was purified from pituitary by chromatography on DEAE-Sepharose, chromatofocusing, butyl-Sepharose, and Sephacryl S-200. Characterization showed that the bACT-like protein was a potent inhibitor of PTP (Ki,app value of 2.2 nM) as well as an effective inhibitor of chymotrypsin (Ki,app value of 2.3 nM). Furthermore, the bACT-like protein formed sodium dodecyl sulfate-stable complexes with chymotrypsin, which is typical of serpin protease inhibitors. Importantly, PTP formed sodium dodecyl sulfate-stable complexes with human ACT, suggesting that PTP's cleavage specificity may resemble the reactive center of ACT. PTP cleavage of enkephalin-containing peptides at the NH2-terminal side of paired basic residues (Lys-Arg, Arg-Arg, Lys-Lys), flanking the COOH terminus of (Met)enkephalin (Tyr-Gly-GLy-Phe-Met), indicates methionine at the P1 position. PTP cleavage of peptide-methylcoumarin amide and peptide-p-nitroanilide substrates demonstrated specificity for paired basic and monobasic residues, as well as a role for methionine in PTP's cleavage site. These results showing PTP's ability for processing at a methionine residue which resembles the P1 specificity of ACT are compatible with inhibition of PTP by ACT. These findings are the first demonstration of the involvement of a protease inhibitor in neuropeptide precursor processing. The known developmental regulation of ACT in brain and significant amounts of ACT in amyloid plaques of Alzheimer's disease suggest a possible role for PTP in the maturation of peptidergic neurons.

Simian T-cell leukemia virus type I infection in captive baboons

Human T-cell leukemia virus type (HTLV-I) is a type C retrovirus that has been linked to both adult T-cell leukemia and neurological disorders in humans. Baboons and other Old World non-human primates harbor a related virus termed simian T-cell leukemia virus type 1 (STLV-I), which may also be associated with neoplastic disease. To explore the utility of the baboon as a model for HTLV-I infection and disease, 329 baboons from a colony of 3200 at the Southwest Foundation for Biomedical Research (SFBR) were analyzed for the presence of antibodies against STLV-I. An overall seroprevalence rate of > 40% was found, with higher rates in females versus males. Furthermore, seroprevalence rates increased dramatically with age, reaching greater than 80% in animals over the age of 16. Molecular and antigenic analysis of proviral DNA isolated from both tumor tissue and a cell line isolated from a baboon with non-Hodgkin's lymphoma (NHL) indicates that STLV-I in this colony is closely related to HTLV-I. Furthermore, monoclonally integrated provirus isolated from lymphoma tissue was detected, strongly implicating STLV-I in the etiology of this malignancy. DNA primer pairs homologous to HTLV-I sequences amplified both HTLV-I and STLV-I, but not HTLV-II, providing further evidence for a close genetic relationship between baboon-derived STLV-I and HTLV-I. The detailed study of a large population of naturally infected baboons may therefore shed some light into the complex processes required for the induction of disease associated with HTLV-I infection in humans.

Shear bond strength of two resin adhesives for acid-etched metal prostheses

This study compared the shear bond strength of Panavia EX and Comspan Opaque adhesive resins with electrolytically etched or sandblasted Rexillium III or Litecast B metals bonded to extracted teeth. An analysis of variance revealed that there is no difference in bonding strength among etched or sandblasted Rexillium III metal with either Panavia EX or Comspan Opaque resins. With Litecast B metal, sandblasting produced a greater bond strength than etching with Panavia Ex resin (38.19 MPa sandblasted; 30.53 MPa etched). Conversely, Comspan Opaque resin had a value of 30.10 MPa etched and 15.40 MPa sandblasted. The etched Rexillium III and Panavia EX resins recorded a greater bond strength (38.38 MPa) than Comspan Opaque resin (27.83 MPa) or sandblasted Rexillium III metal (Rexillium III 34.74 MPa; Comspan Opaque 20.39 MPa) and Litecast B metal (Panavia EX 38.19 MPa; Comspan Opaque 15.40 MPa). Eighty percent of the failures occurred at the cement-metal interface with both cements.

Cytomorphologic features of sputum samples from marijuana smokers

Histopathologic evidence in recent literature suggests that habitual, heavy marijuana smoking causes changes in the bronchial airways similar to changes seen in older, habitual cigarette smokers. The cytologic effects of marijuana smoking on the bronchial airways were investigated utilizing a quantitative analysis of sputum. Levels of macrophages (pigmented and nonpigmented), neutrophils, mucus, mucous spirals, and columnar and benign metaplastic cells were measured. The presence or absence of dysplasia, "purse" cells, eosinophils, reactive bronchial lining cells, and benign bronchial hyperplasia was noted. Results were compared across three groups of 25 subjects each: never cigarette or marijuana smokers: marijuana only smokers: and in cigarette only smokers. Results indicate that cytomorphologic changes observed in habitual marijuana smokers are similar to changes observed in tobacco smokers and much different than those observed in nonsmokers. These cytologic findings are similar to those described in other studies from specimens obtained at bronchoscopy.

A comparison of particulate allogeneic and particulate autogenous bone grafts into maxillary alveolar clefts in dogs

Bilateral complete mature alveolar clefts with oronasal fistulae were surgically created in dogs to directly compare the rate and quantity of bone formation between autogenous particulate bone and cancellous marrow, undecalcified freeze-dried allogeneic bone, and controls of repaired clefts without bone graft material. This study demonstrated autogenous particulate bone and marrow to be the superior graft material, although the allogeneic bone demonstrated bone formation through inductive mechanisms. The bone formation through induction was delayed compared with the autogenous graft system, and was quantitatively insufficient to support eruptive or orthopedic forces.

Circannual rhythms of plasma testosterone and luteinizing hormone levels in golden-mantled ground squirrels (Spermophilus lateralis)

Male squirrels, born approximately June 1 and kept under constant conditions of photoperiod (14 h of light per day) and temperature (23 +/- 2 degrees C) from birth, manifested circannual rhythms in plasma testosterone (T) and luteinizing hormone (LH) levels. Blood samples were collected once per month for 22 months and hormone levels determined by radioimmunoassay. Testosterone levels were low or undetectable ( less than or equal to 0.05 ng/ml) between October and January of the first year, and began increasing in February and peaked during April and May (approx. 4.5 ng/ml). By August of the second year T had declined to low levels which were maintained through January (0.05 ng/ml). The cycle then repeated, with T titers elevated during April and May of the second year. LH levels were undetectable (less than or equal to ng/ml) throughout most of the first 8 months of life; LH peaks were reached by individual animals between March and July. There was a close correspondence between seasonal peaks and troughs of testosterone and those in LH. The circannual pattern of plasma T and LH also was documented for a group of field-trapped males (less than or equal to 11 months old) maintained under similar conditions and bled at monthly intervals for 14 consecutive months. Rhythms of plasma T and LH persisted with a period of 11 to 12 months under constant conditions and thus qualify as circannual cycles.