Surgical management of perianal fistula using an ovine forestomach matrix implant.

PURPOSE: Invasive surgical management of cryptoglandular perianal fistulas (PF) is challenging because of high recurrence rates and the potential for injury to the sphincter complex. In the present technical note, we introduce a minimally invasive treatment for PF using a perianal fistula implant (PAFI) comprising ovine forestomach matrix (OFM). METHODS: This retrospective observational case series highlights 14 patients who had undergone a PAFI procedure at a single center between 2020 and 2023. During the procedure, previously deployed setons were removed and tracts were de-epithelialized with curettage. OFM was rehydrated, rolled, passed through the debrided tract, and secured in place at both openings with absorbable suture. Primary outcome was fistula healing at 8 weeks, and secondary outcomes included recurrence or postoperative adverse events. RESULTS: Fourteen patients underwent PAFI using OFM with a mean follow-up period of 37.6 ± 20.1 weeks. In follow-up, 64% (n = 9/14) had complete healing at 8 weeks and all remained healed, except one at last follow-up visit. Two patients underwent a second PAFI procedure and were healed with no recurrence at the last follow-up visit. Of all patients that healed during the study period (n = 11), the median time to healing was 3.6 (IQR 2.9-6.0) weeks. No postprocedural infections nor adverse events were noted. CONCLUSIONS: The minimally invasive OFM-based PAFI technique for PF treatment was demonstrated to be a safe and feasible option for patients with trans-sphincteric PF of cryptoglandular origin.

Robotic trans-abdominal transplant nephrectomy for a failed renal allograft.

Minimally invasive surgery for removal of a failed renal allograft has not previously been reported. Herein, we report the first robotic trans-abdominal transplant nephrectomy (TN). A 34-year-old male with Alport's syndrome lost function of his deceased donor allograft after 12 years and presented with fever, pain over his allograft and hematuria. The operation was performed intra-abdominally using the Da Vinci Robotic Surgical System with four trocars. The total operative time was 235 min and the estimated blood loss was less than 25 cm(3). There were no peri-operative complications observed and the patient was discharged to home less than 24 h postoperatively. The utilization of robotic technology facilitated the successful performance of a minimally invasive, trans-abdominal TN.

Simultaneous thoracic and abdominal transplantation: can we justify two organs for one recipient?

Simultaneous thoracic and abdominal (STA) transplantation is controversial because two organs are allocated to a single individual. We studied wait-list urgency, and whether transplantation led to successful outcomes. Candidates and recipients for heart-kidney (SHK), heart-liver (SHLi), lung-liver (SLuLi) and lung-kidney (SLuK) were identified through the United Network for Organ Sharing (UNOS) and outcomes were compared to single-organ transplantation. Since 1987, there were 1801 STA candidates and 836 recipients. Wait-list survival at 1- and 3 years for SHK (67.4%, 40.8%; N = 1420), SHLi (65.7%, 43.6%; N = 218) and SLuLi (65.7%, 41.0%; N = 122), was lower than controls (p < 0.001), whereas for SLuK (65.0%, 51.6%; N = 41) it was comparable (p = 0.34). All STA groups demonstrated similar 1- and 5 years posttransplant survival to thoracic controls. Compared to abdominal controls, 1- and 5 years posttransplant survival in SHK (85.3%, 74.0%; N = 684), SLuLi (75.5%, 59.0%; N= 42) and SLuK (66.7%, 55.6%; N = 18) was decreased (p < 0.01), but SHLi (85.9%, 74.3%; N = 92) was comparable (p = 0.81). In summary, STA candidates had greater risk of wait-list mortality compared to single-organ candidates. STA outcomes were similar to thoracic transplantation; however, outcomes were similar to abdominal transplantation for SHLi only. Although select patients benefit from STA, risk-exposure variables for decreased survival should be identified, aiming to eliminate futile transplantation.

Risk of window period hepatitis-C infection in high infectious risk donors: systematic review and meta-analysis.

The OPTN classifies high infectious risk donors (HRDs) based on criteria originally intended to identify people at risk for HIV infection. These donors are sometimes referred to as 'CDC high risk donors' in reference to the CDC-published guidelines adopted by the OPTN. However, these guidelines are also being used to identify deceased donors at increased risk of window period (WP) hepatitis C virus (HCV) infection, although not designed for this purpose. The actual risk of WP HCV infection in HRDs is unknown. We performed a systematic review of 3476 abstracts and identified 37 eligible estimates of HCV incidence in HRD populations in the United States/Canada. Pooled HCV incidence was derived and used to estimate the risk of WP infection for each HRD category. Risks ranged from 0.26 to 300.6 per 10,000 donors based on WP for ELISA and 0.027 to 32.4 based on nucleic acid testing (NAT). Injection drug users were at highest risk (32.4 per 10,000 donors by NAT WP), followed by commercial sex workers and donors exhibiting high risk sexual behavior (12.3 per 10,000), men who have sex with men (3.5 per 10,000), incarcerated donors (0.8 per 10,000), donors exposed to HIV infected blood (0.4 per 10,000) and hemophiliacs (0.027 per 10,000). NAT reduced WP risk by approximately 10-fold in each category.

Risk of window period HIV infection in high infectious risk donors: systematic review and meta-analysis.

The OPTN defines high risk donors (HRDs), colloquially known as 'CDC high risk donors', as those thought to carry an increased risk of HIV window period (WP) infection prior to serologic detectability. However, the true risk of such infection remains unknown. To quantify the risk of WP infection in each HRD behavior category, we performed a systematic review and meta-analysis of studies of HIV prevalence and incidence. Of 3476 abstracts reviewed, 27 eligible studies of HIV infection in HRD populations were identified. Pooled HIV incidence estimates were calculated for each category of HRD behavior and used to calculate the risk of WP HIV infection. Risks ranged from 0.09-12.1 per 10 000 donors based on WP for ELISA and 0.04-4.9 based on nucleic acid testing (NAT), with NAT reducing WP risk by over 50% in each category. Injection drug users had the greatest risk of WP infection (4.9 per 10 000 donors by NAT WP), followed by men who have sex with men (4.2:10 000), commercial sex workers (2.7:10 000), incarcerated donors (0.9:10 000), donors exposed to HIV through blood (0.6:10 000), donors engaging in high-risk sex (0.3:10 000) and hemophiliacs (0.035:10 000). These estimates can help inform patient and provider decision making regarding HRDs.

Higher Volume at Time of Breast Conserving Surgery Reduces Re-Excision in DCIS.

Purpose. The purpose of this study was to compare the surgical and pathological variables which impact rate of re-excision following breast conserving therapy (BCS) with or without concurrent additional margin excision (AM). Methods. The pathology database was queried for all patients with DCIS from January 2004 to September 2008. Pathologic assessment included volume of excision, subtype, size, distance from margin, grade, necrosis, multifocality, calcifications, and ER/PR status. Results. 405 cases were identified and 201 underwent BCS, 151-BCS-AM, and 53-mastectomy. Among the 201 BCS patients, 190 underwent re-excision for close or involved margins. 129 of these were treated with BCS and 61 with BCS-AM (P < .0001). The incidence of residual DCIS in the re-excision specimens was 32% (n = 65) for BCS and 22% (n = 33) for BCS-AM (P < .05). For both the BCS and the BCS-AM cohorts, volume of tissue excised is inversely correlated to the rate of re-excision (P = .0284). Multifocality (P = .0002) and ER status (P = .0382) were also significant predictors for rate of re-excision and variation in surgical technique was insignificant. Conclusions. The rate of positive margins, re-excision, and residual disease was significantly higher in patients with lower volume of excision. The performance of concurrent additional margin excision increases the efficacy of BCS for DCIS.

Reproductive biology of the epiphytic bromeliad Werauhia gladioliflora in a premontane tropical forest.

The floral phenology, fruit and seed production, and self-compatibility of Werauhia gladioliflora, an epiphytic bromeliad with a wide distribution, were studied in a premontane forest in the Monteverde area in Costa Rica. The species presents the pollination syndrome of chiropterophily, and it is visited by the small bats Hylonycteris underwoodi and Glossophaga commissarisi (Glossophaginae). The population flowering period extended from October to early December (end of rainy season) and seed dispersal occurred from February to April (dry season). Most plants opened a single flower per night, either every day or at one-day intervals during the flowering period. In natural conditions, the average fruit set amounted to almost half of the potential output, but individual fecundity (number of seeds) remained high. Seed number per fruit and germination capacity after artificial selfing and out-crossing treatments did not differ from natural pollination conditions. Werauhia gladioliflora exhibited high levels of autonomous self-pollination and self-compatibility at the individual and population level, characters associated with the epiphytic habitat. These reproductive traits are also associated with early colonizer species, yet life history traits, such as seed dispersal, seedling establishment success, and growth, are likely to have a major role in determining the presence of this species in the successional vegetation patches scattered over the studied premontane area.

The social and medical construction of lactation pathology.

Beginning in the 1880s, many mothers reported breastfeeding difficulties. Doctors blamed the stress of urban life. The "bad" human milk invariably produced by the mammary glands of urban women, some physicians charged, harmed babies as surely as the dirty and adulterated cow's milk common to the late nineteenth-century city. Mothers and pediatricians proved unusually susceptible to believing this allegation. Mothers, just learning about the germ theory of disease and anxious about protecting their babies from unseen microbes, found themselves gratefully relying on "scientific" food rather than on their own, apparently faulty, bodies. And pediatricians no longer had to defend their new specialty. Now they could point to the need for improved artificial food-given women's growing inability to lactate-as one justification for their specialty's existence. Under the influence of these mothers and doctors, the notion that human lactation is an unreliable body function became a cultural truth that has persisted unabated to the present day.

Muscle spindle reinnervation following phenol block.

Infusion of phenol into peripheral nerves is used clinically to manage spasticity. It produces relief of symptoms by chemical denervation. We simulated the clinical procedure by bathing the lateral plantar nerve of rats in 7% phenol solution for 20 min. We studied the innervation of muscle spindles in the plantar lumbrical muscles of untreated rats and in rats 4 and 6 weeks after a single phenol block. Spindles were identified by the immunoreactivity of nuclear bag(1) fibers to slow tonic myosin (antibody ALD 19). The integrity of the sensory and motor reinnervation of spindles was evaluated using a monoclonal antibody specific for a high molecular weight neurofilament protein. Four weeks after phenol block, muscle spindles were difficult to find, as their immunoreactivity to antibody ALD 19 was reduced. In those spindles studied, most (>80%) were completely denervated. The remainder of which were innervated by afferents only. None received efferent (gamma) innervation. After 6 weeks, spindles were readily identified and nearly all (>90%) received recognizable afferent innervation. A much smaller number (38%) received gamma innervation. Phenol block thus results in a complete denervation of muscle spindles, followed by a fairly rapid sensory reinnervation. Reinnervation by gamma motor neurons is either incomplete or significantly delayed.

4-Bromomethyl-7-methoxycoumarin and analogues as derivatization agents for high-performance liquid chromatography determinations: a review.

A major part of modern analytical problem solving deals with the trace level determination of organic compounds and contaminants in biomedical, food and environmental samples. In the analysis of these samples chromatographic techniques play a predominant role. Unfortunately, however, even the combined force of an efficient separation plus a sophisticated mode of detection does not always create sufficient selectivity and/or sensitivity for the final goal to be attained. In such cases, special attention has to be devoted to derivatization or conversion of the analyte(s) of interest (for improved detection selectivity and/or sensitivity) and sample pretreatment (for trace enrichment and clean-up). The above is especially true when, as is often the case today, relatively polar drugs, endogenous compounds, additives or environmental pollutants and/or their (bio)-degradation products have to be determined. For such classes of compounds high-performance column liquid chromatography (HPLC) generally is the preferred method of separation. Reversed-phase HPLC with fluorescence detection is a powerful means of analysis for compounds which possess native fluorescence. They are, however, relatively few in number. In order to make the method useful for a much wider range of analytes, one can therefore resort to derivatization (labelling) or other means of analyte conversion to obtain highly fluorescent reaction products, which can then be detected with the required selectivity and sensitivity. 4-Bromomethyl-7-methoxycoumarin is often used as fluorescent label for the determination of compounds possessing a carboxylic group. About 8% of the biologically interesting analytes--ranging from polar amino acids and peptides to apolar fatty acids--possess such a group.(ABSTRACT TRUNCATED AT 250 WORDS)

Automated precolumn fluorescence labelling by carbodiimide activation of N-acetylaspartate and N-acetylaspartylglutamate applied to an HPLC brain tissue analysis.

An automated method is described to couple carboxyl-containing metabolites to the fluorophore 2-aminoanthracene in aqueous solution (containing 75% methanol) in the presence of N,N-dicyclohexylcarbodiimide. The reaction was optimized for N-acetylaspartate (N-Ac-Asp) and N-acetylaspartylglutamate (N-Ac-Asp-Glu). The reactions occurred within 5 min at room temperature in the presence of 0.5-2 mM HCl. At concentrations of electrolytes exceeding 10 mM the coupling reaction became suboptimal. Derivatization was performed in a commercial precolumn derivatization unit. Additional tubing was needed to provide the reagents prior to reversed-phase HPLC and fluorescence detection. The assay is linear over at least three orders of magnitude; as little as 1 pmol could reproducibly be assayed in 100 micrograms wet weight brain tissue extracted with a mixture of methanol and 4 mM HCl (9:1, v/v). N-Ac-Asp and N-Ac-Asp-Glu levels in several brain regions and spinal cord were similar to those so far reported. The compounds could not be detected in peripheral tissue. The advantages, prospects and limitations of the present approach over existing methods to estimate water-soluble carboxylic acids is discussed.

The extracellular concentration of the anti-epileptic drug valproate in the rat brain as determined with microdialysis and an automated HPLC procedure.

The cellular and extracellular brain concentration of valproic acid in freely moving rats has been estimated after intravenous injection of sodium valproate. Some rats were provided with a stereotaxically implanted dialysis probe in the striatum and a cannula in the heart through which the drug was injected and which allowed regular removal of blood. In other rats tissue levels of valproic acid were determined 5 and 90 min after drug injection. Valproic acid was determined by an automated precolumn derivatization procedure followed by HPLC separation and fluorimetric detection. Extracellular concentration was proportional to the blood concentration at every time interval, indicating rapid exchange of the drug between the two compartments. About 50% of the striatal content of valproate was in extracellular space. The experiments demonstrated the usefulness of microdialysis to estimate both the extracellular concentration and the average cellular drug levels, provided a sensitive analysis procedure is available.