Risk factors for post-operative VTE following colorectal surgery: Is caprini score enough?

BACKGROUND

Post-operative colorectal venous thromboembolism (VTE) rates range between 1 and 3%. Often, surgeons utilize risk assessment models, like the modified Caprini, to determine need for prophylaxis. However, studies reveal additional unaccounted risk factors like preoperative serum albumin level, perioperative blood transfusion, emergency surgery, and preoperative steroid use.

METHODS

This was a multicenter, retrospective study conducted between January 2021-December 2021. The primary endpoint was to assess the VTE rate within 30 days post-operatively.

RESULTS

Overall, incidence rate was 1.75%. Of these, 53% underwent urgent/emergent surgery and 60% had perioperative blood transfusions. Twelve patients had a known preoperative serum albumin level, with 66% being less than 3.5 ​g/dL. Only 30% of patients had a high Caprini risk score. No patient had preoperative steroid use.

CONCLUSION

The study suggests considering urgent/emergent surgeries, low preoperative albumin levels, and blood transfusions for enhanced VTE screening and prophylaxis in post-operative colorectal patients.

Household transmission of SARS-CoV-2 in a rural area in South Africa

BACKGROUND

Patterns of SARS-CoV-2 spread have varied by geolocation, with differences in seroprevalence between urban and rural areas, and between waves. Household spread of SARS-CoV-2 is a known source of new COVID-19 infections, with rural areas in sub-Saharan Africa being more prone than urban areas to COVID-19 transmission because of limited access to water in some areas, delayed health- seeking behaviour and poor access to care.

OBJECTIVES

To explore SARS-CoV-2 infection incidence and transmission in rural households in South Africa (SA).

METHODS

We conducted a prospective household cluster investigation between 13 April and 21 July 2021 in the Matjhabeng subdistrict, a rural area in Free State Province, SA. Adults with SARS-CoV-2 confirmed by polymerase chain reaction (PCR) tests (index cases, ICs) and their household contacts (HCs) were enrolled. Household visits conducted at enrolment and on days 7, 14 and 28 included interviewer- administered questionnaires and respiratory and blood sample collection for SARS-CoV-2 PCR and SARS-CoV-2 immunoglobulin G serological testing, respectively. Co-primary cases were HCs with a positive SARS-CoV-2 PCR test at enrolment. The incidence rate (IR), using the Poisson distribution, was HCs with a new positive PCR and/or serological test per 1 000 person-days. Associations between outcomes and HC characteristics were adjusted for intra-cluster correlation using robust standard errors. The secondary infection rate (SIR) was the proportion of new COVID-19 infections among susceptible HCs.

RESULTS

Among 23 ICs and 83 HCs enrolled, 10 SARS-CoV-2 incident cases were identified, giving an IR of 5.8 per 1 000 person-days (95% confidence interval (CI) 3.14 - 11.95). Households with a co-primary case had higher IRs than households without a co-primary case (crude IR 14.16 v. 1.75, respectively; p=0.054). HIV infection, obesity and the presence of chronic conditions did not materially alter the crude IR. The SIR was 15.9% (95% CI 7.90 - 29.32). Households with a lower household density (fewer household members per bedroom) had a higher IR (IR 9.58; 95% CI 4.67 - 21.71) than households with a higher density (IR 3.06; 95% CI 1.00 - 12.35).

CONCLUSION

We found a high SARS-CoV-2 infection rate among HCs in a rural setting, with 48% of households having a co-primary case at the time of enrolment. Households with co-primary cases were associated with a higher seroprevalence and incidence of SARS-CoV-2. Sociodemographic and health characteristics were not associated with SARS-CoV-2 transmission in this study, and we did not identify any transmission risks inherent to a rural setting.

Predictive factors of first-time failure on the American Board of Colorectal Surgery certifying and qualifying examinations

Objective

To discover if first-attempt failure of the American Board of Colon and Rectal Surgery (ABCRS) board examination is associated with surgical training or personal demographic characteristics.

Methods

Current colon and rectal surgery program directors in the United States were contacted via email. Deidentified records of trainees from 2011 to 2019 were requested. Analysis was performed to identify associations between individual risk factors and failure on the ABCRS board examination on the first attempt.

Results

Seven programs contributed data, totaling 67 trainees. The overall first-time pass rate was 88% (n = 59). Several variables demonstrated potential for association, including Colon and Rectal Surgery In-Training Examination (CARSITE) percentile (74.5 vs 68.0, P = 0.09), number of major cases in colorectal residency (245.0 vs 219.2, P = 0.16), >5 publications during colorectal residency (75.0% vs 25.0%, P = 0.19), and first-time passage of the American Board of Surgery certifying examination (92.5% vs 7.5%, P = 0.18).

Conclusion

The ABCRS board examination is a high-stakes test, and training program factors may be predictive of failure. Although several factors showed potential for association, none reached statistical significance. Our hope is that by increasing our data set, we will identify statistically significant associations that can potentially benefit future trainees in colon and rectal surgery.

Measuring gender norms about relationships in early adolescence: Results from the global early adolescent study

Introduction

Gender norms are increasingly recognized as drivers of health and wellbeing. While early adolescence constitutes a critical window of development, there is limited understanding about how adolescents perceive gender relations across different cultural settings. This study used a mixed-method approach, grounded in the voices of young people around the world, to construct and test a cross-cultural scale assessing the perceptions of gender norms regulating romantic relationships between boys and girls in early adolescence.

Methods

The study draws on the Global Early Adolescent study (GEAS), a study focusing on gender norms and health related outcomes over the course of adolescence in urban poor settings worldwide. In-depth interviews were first conducted among approximately 200 adolescents between 10–14 years in seven sites across 4 continents to identify common scripts guiding romantic relations in early adolescence. These scripts were then transformed into a multidimensional scale. The scale was tested among 120 adolescents in each of 14 GEAS sites, followed by a second pilot among 75 adolescents in six sites. We evaluated the psychometric criteria of each sub-scale using principal component analysis, and parallel analysis, followed by exploratory factor analysis to guide the selection of a more parsimonious set of items.

Results

Results suggested a two-factor structure, consisting of an “adolescent romantic expectations” subscale and a “Sexual Double Standard” subscale. Both subscales yielded high internal validity in each site, with polychoric Cronbach alpha values above 0.70 with the exception of Kinshasa for the adolescent romantic expectations scale (0.64) and Hanoi for the sexual double standard scale (0.61).

Conclusion

This study reveals common perceptions of gendered norms about romantic engagement in early adolescence, normative for both sexes, but socially valued for boys while devaluated for girls. The findings illustrate that social hierarchies of power in romantic relationships form early in adolescence, regardless of cultural setting.

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Gender norms about romantic relationships prevail across diverse cultures.

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New cross-cultural scales measure early adolescents’ perceptions of gender norms;

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Adolescent romantic relations are viewed as normative but damaging for girls;

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Even before sexual activity, adolescents understand societal expectations about relationships;

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Social hierarchies of power in relationships form in early adolescence.

Metastatic Adenocarcinoma of Unknown Origin Presenting as Small Bowel Perforation

Metastatic malignant tumors that originate from occult primaries are defined as “cancers of unknown origin.” We herein present the case of a 59-year-old man who presented with small bowel perforation secondary to metastatic adenocarcinoma of an unknown primary site. Imaging exhibited two pulmonary nodules, neither of which was dominant, along with mediastinal and retroperitoneal lymphadenopathy. Immunohistochemical profiling of the small bowel biopsy specimens revealed the tumor was most likely pulmonary in origin.

Minimally invasive treatment of pancreatic necrosis

AIM: To systematically review these minimally invasive approaches to infected pancreatic necrosis.

METHODS: We used the MEDLINE database to investigate studies between 1996 and 2010 with greater than 10 patients that examined these techniques. Using a combination of Boolean operators, reports were retrieved addressing percutaneous therapy (341 studies), endoscopic necrosectomy (574 studies), laparoscopic necrosectomy via a transperitoneal approach (148 studies), and retroperitoneal necrosectomy (194 studies). Only cohorts with at least 10 or more patients were included. Non-English papers, letters, animal studies, duplicate series and reviews without original data were excluded, leaving a total of 27 studies for analysis.

RESULTS: Twenty-seven studies with 947 patients total were examined (eight studies on percutaneous approach; ten studies on endoscopic necrosectomy; two studies on laparoscopic necrosectomy via a transperitoneal approach; five studies on retroperitoneal necrosectomy; and two studies on a combined percutaneous-retroperitoneal approach). Success rate, complications, mortality, and number of procedures were outcomes that were included in the review. We found that most published reports were retrospective in nature, and thus, susceptible to selection and publication bias. Few reports examined these techniques in a comparative, prospective manner.

CONCLUSION: Each minimally invasive approach though was found to be safe and feasible in multiple reports. With these new techniques, treatment of infected pancreatic necrosis remains a challenge. We advocate a multidisciplinary approach to this complex problem with treatment individualized to each patient.

Impact of minimally invasive surgery on the treatment of benign esophageal disorders

Thanks to the development of minimally invasive surgery, the last 20 years have witnessed a change in the treatment algorithm of benign esophageal disorders. Today a laparoscopic operation is the treatment of choice for esophageal achalasia and for most patients with gastroesophageal reflux disease. Because the pathogenesis of achalasia is unknown, treatment is palliative and aims to improve esophageal emptying by decreasing the functional obstruction at the level of the gastro-esophageal junction. The refinement of minimally invasive techniques accompanied by large, multiple randomized control trials with long-term outcome has allowed the laparoscopic Heller myotomy and partial fundoplication to become the treatment of choice for achalasia compared to endoscopic procedures, including endoscopic botulinum toxin injection and pneumatic dilatation. Patients with suspected gastroesophageal reflux need to undergo a thorough preoperative workup. After establishing diagnosis, treatment for gastroesophageal reflux should be individualized to patient characteristics and a decision about an operation made jointly between surgeon and patient. The indications for surgery have changed in the last twenty years. In the past, surgery was often considered for patients who did not respond well to acid reducing medications. Today, the best candidate for surgery is the patient who has excellent control of symptoms with proton pump inhibitors. The minimally invasive approach to antireflux surgery has allowed surgeons to control reflux in a safe manner, with excellent long term outcomes. Like achalasia and gastroesophageal reflux, the treatment of patients with paraesophageal hernias has also seen a major evolution. The laparoscopic approach has been shown to be safe, and durable, with good relief of symptoms over the long-term. The most significant controversy with laparoscopic paraesophageal hernia repair is the optimal crural repair. This manuscript reviews the evolution of these techniques.

Evolution of the minimally invasive treatment of esophageal achalasia

Thanks to the advent of laparoscopic techniques, the last decade and a half have witnessed a radical change in the treatment of esophageal achalasia. Because of the high success rate of the laparoscopic Heller myotomy, surgery has now become in many centers the first modality of treatment for achalasia. This shift in the treatment algorithm reflects the fact that laparoscopic Heller myotomy with partial fundoplication outperforms nonsurgical approaches, such as balloon dilatation and intrasphincteric botulinum toxin injection.

Evolution of the minimally invasive treatment of esophageal achalasia

Thanks to the advent of laparoscopic techniques, the last decade and a half have witnessed a radical change in the treatment of esophageal achalasia. Because of the high success rate of the laparoscopic Heller myotomy, surgery has now become in many centers the first modality of treatment for achalasia. This shift in the treatment algorithm reflects the fact that laparoscopic Heller myotomy with partial fundoplication outperforms nonsurgical approaches, such as balloon dilatation and intrasphincteric botulinum toxin injection.

Tetracycline-inducible systems for Drosophila

Since their inception, tetracycline (Tet)-inducible systems have become the method of choice for transgenic research. The Tet-Off systems have a number of advantages, including robust target induction using a relatively benign effector molecule. However, use of the Tet-On system has been fraught with difficulties, including high background expression in the absence of effector molecules and inconsistent gene induction. Recently, second generation Tet-On transactivators (TAs) have been described. In HeLa cells, they are far more efficient than the original reverse TA protein, and they exhibit lower background activity in the absence of effectors. Here we examine the most promising TA in transgenic Drosophila and characterize its in vivo properties. We report that low levels of doxycycline, when added to normal fly food, efficiently and rapidly induce target transgenes in adults, larvae, and embryos. This TA is superior to all other Tet-On proteins, and its performance is comparable to that of the widely used Tet-Off TA. In addition, combining the improved Tet-On TA with the Gal4-UAS (upstream-activating sequence) system produces robust, spatially restricted, temporally controlled transgene induction. Because this Tet-On TA is significantly more efficient than previous ones used in Drosophila, it is also possible to modulate gene induction by controlling the dosage of the antibiotic in the food.

Skeletal muscle abnormalities associated with occupational exposure to mercury vapours

There is scarce information on the possible effects of chronic exposure to mercury on skeletal muscle. Dental personnel are frequently exposed to inhalation of metallic mercury vapours. The skeletal muscle of five technicians and one dentist (females, age 36-55) was studied. All of them presented symptoms of chronic mercury poisoning. Needle biopsy was taken from the quadriceps femoris muscle and samples were prepared for light microscope histochemistry and for transmission electron microscopy. Selective atrophy of type IIB muscle fibres was found in patients, and in one of them there was fibre grouping. Most of the muscles showed increased fibre area per capillary. Atrophy was confirmed by the ultrastructural study, demonstrating increase of intermyofibrillar spaces, loss of myofibrils or complete disappearance in some fibres, and sarcolemmal foldings. Splitting of the fibres was also found. Some capillaries were altered, showing endothelial infoldings into the lumen, thickened basement membrane and partial or total occlusion. The alterations found in muscle may be secondary to nerve damage, to ischemia caused by capillary lesion and/or to a direct effect of mercury on muscle fibre proteins.

Ultrastructural alterations in the adrenal gland cortex of mice experimentally infected with a Venezuelan isolate of Trypanosoma evansi

The ultrastructural study of adrenal gland from mice experimentally infected with Trypanosoma evansi, in addition to intravascular and intracellular trypanosomes, showed different degrees of cortical cell alterations and capillary wall modifications. Beside its biological scope, these results suggest a role for the adrenal cortex to partake in Surra's etiopathogenesis and describe for the very first time a T. evansi intracellular stage.

Spatial and temporal targeting of gene expression in Drosophila by means of a tetracycline-dependent transactivator system

In order to evaluate the efficiency of the tetracycline-regulated gene expression system in Drosophila, we have generated transgenic lines expressing a tetracycline-controlled transactivator protein (tTA), with specific expression patterns during embryonic and larval development. These lines were used to direct expression of a tTA-responsive promoter fused to the coding region of either the beta-galactosidase or the homeotic protein Antennapedia (ANTP), under various conditions of tetracycline treatment. We found that expression of beta-galactosidase can be efficiently inhibited in embryos and larvae with tetracycline provided in the food, and that a simple removal of the larvae from tetracycline exposure results in the induction of the enzyme in a time- and concentration-dependent manner. Similar treatments can be used to prevent the lethality associated with the ectopic expression of ANTP in embryos and, subsequently, to control the timing of expression of the homeoprotein ANTP specifically in the antennal imaginal disc. Our results show that the expression of a gene placed under the control of a tetracycline-responsive promoter can be tightly controlled, both spatially by the regulatory sequences driving the expression of tTA and temporally by tetracycline. This provides the basis of a versatile binary system for controlling gene expression in Drosophila, with an additional level of regulation as compared to the general method using the yeast transcription factor GAL4.

In vivo analysis of scaffold-associated regions in Drosophila: a synthetic high-affinity SAR binding protein suppresses position effect variegation

Scaffold-associated regions (SARs) were studied in Drosophila melanogaster by expressing a synthetic, high-affinity SAR-binding protein called MATH (multi-AT-hook), which consists of reiterated AT-hook peptide motifs; each motif is known to recognize a wide variety of short AT-rich sequences. MATH proteins were expressed specifically in the larval eye imaginal discs by means of the tetracycline-regulated transactivation system and tested for their effect on position effect variegation (PEV). MATH20, a highly potent SAR ligand consisting of 20 AT-hooks, was found to suppress whitemottled 4 variegation. This suppression required MATH20 expression at an early larval developmental stage. Our data suggest an involvement of the high AT-rich SARs in higher order chromatin structure and gene expression.

The cramped gene of Drosophila is a member of the Polycomb-group, and interacts with mus209, the gene encoding Proliferating Cell Nuclear Antigen

We have isolated and molecularly characterized the cramped (crm) gene of Drosophila melanogaster, and show that it can be classified as a Polycomb-group (Pc-G) gene. crm mutants exhibit typical Pc-G mutant phenotypes, reminiscent of ectopic homeotic gene expression, with additional sex comb teeth found on mesothoracic and metathoracic legs, and proximodistal transformations of the tarsal segments. crm encodes an 693 amino acids protein, with no significant homology to known proteins. We used polyclonal antibodies raised against bacterially expressed truncated CRM protein to show that the crm gene product is localized to the nucleus during embryogenesis. This nuclear localization appears to be restricted to S-phase nuclei, as CRM immunostaining disappears at mitosis. We found that this cell-cycle-dependent staining pattern was identical to that of Proliferating Cell Nuclear Antigen (PCNA). Furthermore, we provide evidence for co-localization of CRM and PCNA proteins in salivary gland polytene nuclei, and for a genetic interaction between crm and mus209, the Drosophila gene encoding PCNA. Together, our data suggest that these two proteins are involved in a common regulatory pathway and highlight possible interactions between Pc-G-mediated silencing and DNA replication in Drosophila.

A cytoplasmic actin gene from the silkworm Bombyx mori is expressed in tissues of endodermal origin and previtellogenic germ cells of transgenic Drosophila

A cytoplasmic actin gene from Bombyx mori introduced into Drosophila melanogaster by P-element mediated transformation, is efficiently transcribed in larvae, pupae and adults of the host. The exogenous mRNA has the same size as the one observed in the Bombyx cells and the intron located within the coding region is properly excised, indicating a correct recognition of the exogenous sequences by the Drosophila transcriptional and splicing machineries. The expression of the Bombyx gene in Drosophila tissues was determined by transforming flies with a hybrid gene in which a large part of the Bombyx actin coding sequences was replaced by those of the bacterial lac Z gene. This chimaeric gene is specifically and highly expressed, from the embryo to the adult of the transgenic lines, in tissues of endodermal origin, the midgut and its derivatives, i.e. gastric caeca, the outer layer of the proventriculus, and in the Malpighian tubules. This gene is also expressed, at a lower level, in germ cells but restricted to the sixteen cell cysts during previtellogenesis. The expression of the Bombyx gene during development of transgenic flies was compared to that of the two Drosophila endogenous cytoplasmic actin genes and the results are discussed.

Specific expression of a silk-encoding gene of Bombyx in the anterior salivary gland of Drosophila

Successful expression of genes transferred into distantly related species in which genetic functions have been maintained through evolution has been reported previously. In the case of the silkmoth Bombyx mori and the fruitfly Drosophila melanogaster, both of which produce chorions (eggshells), Bombyx chorion genes are correctly expressed in Drosophila despite their estimated 240-Myr phylogenetic divergence. Here we report that, although Drosophila does not produce silk, mechanisms regulating transcription have been conserved between the salivary gland of the fruitfly and the silk gland of the silkmoth larva.