Multiple human papillomavirus infections and HIV seropositivity as risk factors for abnormal cervical cytology among female sex workers in Nairobi.

We estimated type-specific prevalence of human papillomavirus (HPV) and examined risk factors for abnormal cervical cytology among 296 female sex workers from Nairobi, Kenya. Over half (54%) were infected with a high-risk (HR) HPV type, of which HPV16 and 52 were the most common types. HIV-1 prevalence was 23% and HIV-1 sero-positivity was associated with high-grade cervical lesions, particularly among women with CD4 count less than 500 cells/mm(3) (odds ratio [OR] = 6.9; 95% confidence interval [CI]: 1.7-24.9). Among women who had normal cytology at the time of entry into the study, the risk of having an abnormal Pap smear within one year was significantly elevated for women with multiple HPV types at study entry (adjusted odds ratio [aOR] = 6.0; 95% CI: 2.3-15.7) and with a subset of HR HPV types (aOR = 4.2; 95% CI: 1.6-11.2). Detection of multiple concurrent HPV infections may be a useful marker to identify women at risk of developing precancerous lesions in populations of high HPV prevalence.

Variations in CD4 cell counts among HIV-uninfected and infected women in Uganda and Zimbabwe.

We conducted a cross-sectional study with 208 HIV-uninfected and 188 HIV-infected women in Uganda and Zimbabwe to investigate differences in median CD4 counts. Absolute CD4 counts were determined by flow cytometry. Multivariate analyses were used to examine the association of country and HIV-infection status on CD4 counts. Median CD4 counts were significantly lower in Zimbabwe than in Uganda overall (649 and 783 cells/mm(3), P = 0.009) and among HIV-infected women (470 and 614 cells/mm(3), P = 0.003). In separate multivariable models, CD4 counts were significantly lower in Zimbabwe in HIV-uninfected (P = 0.014) and infected (P < 0.001) women, controlling for age, contraceptive method, education and living with partner status. In a model combining HIV-uninfected and infected women, there was no significant interaction between country and HIV infection status (P = 0.344), suggesting that the relationship between country and CD4 count was not significantly modified by HIV infection status. This study reinforces the importance of establishing country-specific reference CD4 levels as CD4 count continues to be used as a key biomarker in clinical decision-making for HIV-infected individuals in sub-Saharan Africa.

Extradigital glomus tumor as a cause of chronic perianal pain.

Glomus tumor is a rare perivascular benign tumor arising from the Sucquet-Hoyer canal of the normal glomus body, most commonly in the digital areas. We report a serving soldier with such a tumor in an atypical site, the perianal region, presenting with episodic shooting pain. Total surgical excision was performed. Histopathology revealed a well-circumscribed tumor composed of clusters of monotonous polygonal cells surrounding capillary-sized blood vessels. Tumor cells also showed immunopositivity for smooth muscle antigen and vimentin. Following excision, the patient was completely relieved of pain and there was no recurrence on follow-up for 6 months.

Investigation of an outbreak of chikungunya in Malegaon Municipal areas of Nasik district, Maharashtra (India) and its control.

BACKGROUND & OBJECTIVES: An outbreak of chikungunya fever occurred in Malegaon town of Nasik district of Maharashtra state, India during February and March 2006. A total of 4530 fever cases were reported during this period including 1781 cases which were admitted in different hospitals of the town. An entomological and epidemiological investigation was carried out in the affected villages during the outbreak to study the possible causes of the outbreak and to isolate the virus responsible. METHODS: Entomological evaluation was done as per WHO guidelines. Sera samples were collected by venipuncture from clinically suspected chikungunya patients in hospitals and also during house-to-house survey in affected villages. IgM antibodies to dengue virus were detected using IgM capture ELISA (PANBIO) and by "Haemagglutination inhibition test" for detection of antibodies against Chikungunya virus. Acute sera samples were inoculated in cell lines for virus isolation. The isolates were confirmed by RT-PCR. RESULTS: On investigation, it was found that water storage containers like cement tanks, plastic containers or earthen pots placed in front of the individual houses were the potential breeding sites for Aedes aegypti. Entomological survey carried out in the most affected areas revealed high Aedes indices. House, container and breteau indices were found to be 27.2, 16.19 and 35.1, respectively. Out of the 13 acute sera samples collected, virus was isolated in 10 samples. The isolates were confirmed by RT-PCR and sequencing using primers from nsP1 gene of Chikungunya virus (CHIKV, Accession No. EF077609, EF077610). Of the 17 convalescent sera tested, significant level of HI antibodies to CHIKV was detected in five samples. One sample was positive for IgM antibodies against dengue virus. Based on clinico-epidemiological features and laboratory findings, the illness was confirmed to be of chikungunya viral disease. CONCLUSION: Control measures targeting the vector population and personal protective measures against the mosquito bites were instituted. Extensive IEC campaign with the involvement of community and religious leaders helped in containment of the disease.

Reconstruction of Complex Abdominal Wall Defects.

INTRODUCTION: Reconstruction of large abdominal wall defects not amenable to primary closure remains a challenging problem. These defects result from trauma, previous surgery, infection and tumour resection. The primary objectives of abdominal wall reconstructions are to protect abdominal contents and provide functional support. The abdominal wall reconstruction aims at providing basic component parts, i.e. skin, soft tissue and fascia. For large soft tissue defects, pedicled or free flap closure can be used. In clean wounds, fascial replacement is accomplished with synthetic mesh provided there is adequate soft tissue coverage. METHODS: We treated a total of 20 consecutive patients with complex abdominal wall defects utilizing various reconstructive procedures. There were 15 males (75%) and 5 females (25%). The aetiology included dehiscence of laparotomy wounds in eight (40%), following ablative surgery for malignant tumours in seven (35%), trauma in three (15%) and congenital defects in two (10%) cases. The reconstructive procedures consisted of onlay prolene mesh in seven (35%), Gore-Tex (PTFE) dual mesh both as inlay and onlay in five (25%), facial partition release technique in three (15%), inlay prolene mesh covered with omentum and split skin graft in two (10%), inlay prolene mesh covered with expanded skin in two (10%), and Gore-Tex dual mesh covered with latissimus dorsi myocutaneous flap in one (5%) case. Postoperatively none developed mesh infection or extrusion. Three patients with malignant aetiology received postoperative radiotherapy. During follow up, one patient developed ventral hernia cephalad to the repair and one died due to recurrence of abdominal wall malignancy. CONCLUSION: The reconstruction of an abdominal wall defect requires a comprehensive plan of preoperative and post operative care of the patient and aims toward restoration of abdominal structural integrity by a variety of procedures. The use of new biomaterials and tissue expanders provides reliable and durable abdominal wall closure along with good aesthetic results.

Synthesizing cellular intelligence and artificial intelligence for bioprocesses.

Microbial processes operated under realistic conditions are difficult to describe by mechanistic models, thereby limiting their optimization and control. Responses of living cells to their environment suggest that they possess some "innate intelligence". Such responses have been modeled by a cybernetic approach. Furthermore, the overall behavior of a bioreactor containing a population of cells may be described and controlled through artificial intelligence methods. Therefore, it seems logical to combine cybernetic models with artificial intelligence to evolve an integrated intelligence-based strategy that is physiologically more faithful than the current approaches. This possibility is discussed, together with practical considerations favoring a hybrid approach that includes some mathematical modeling.

Neural network designs for poly-beta-hydroxybutyrate production optimization under simulated industrial conditions.

Improvement of the fermentation efficiency of poly-beta-hydroxybutyrate (PHB) may make it competitive with chemically synthesized petroleum-based polymers. One step toward this is optimization of fluid dispersion and the feed rates to a fed-batch bioreactor. In a recent study using a fermentation model, dispersion corresponding to a Peclet number of approximately 20 was shown to maximize the productivity of PHB. Here further improvement has been investigated using neural optimization. A comparison of seven neural topologies has shown that while feed-forward and radial basis neural networks are computationally efficient, recurrent networks generate higher concentrations of PHB. All networks enhanced the productivity by 16-93% over model-based optimization.

Effect of fluid dispersion on cybernetic control of microbial growth on substitutable substrates.

Many fermentation media contain two or more substrates, which a microorganism utilizes for similar purposes. Depending on the conditions prior to and during a fermentation, the substrates may be utilized in succession or simultaneously. Since it is difficult to portray this behavior through mechanistic models, a cybernetic method was proposed earlier. Here the microorganism chooses the mode of substrate utilization that maximizes its own survival, usually expressed by the growth rate. In a fully dispersed bioreactor, simultaneous utilization generates higher growth rates but leads to low biomass concentrations since this utilization pattern is preferred at low concentrations of the substrates. In this study it has been shown that by allowing less than complete dispersion in the broth it is possible to shift from sequential to simultaneous utilization at high concentrations, thereby enabling both high growth rates and large biomass concentrations. This strategy thus allows the natural incomplete dispersion in large bioreactors to be gainfully exploited.

On the performances of noise filters in the restoration of oscillatory behavior in continuous yeast cultures.

Continuous flow microbial fermentations under industrial conditions are subject to the influx of noise, mainly through the feed stream. Noise upsets the normal deterministic behavior. For continuous cultures of Saccharomyces cerevisiae exhibiting oscillatory responses, four kinds of commonly used noise filters, three algorithmic and one neural, have been compared for their ability to restore noise-free oscillations. An auto-associative neural filter was the best, similar to earlier observations for other organisms under non-oscillatory conditions. This enhances the general applicability of neural filters for industrial scale fermentations.

Extraserosal pedunculated leiomyoma of stomach.

Leiomyoma of the stomach, a type of gastrointestinal stromal tumor, is uncommon. We report a 51-year-old woman with an extraserosal pedunculated leiomyoma of the stomach.

Hepatic resection for benign liver pathology--report of two cases.

Hepatic resection for benign pathology is rare. We report our experience in two patients with hepaticolithiasis. One patient underwent left hemihepatectomy with removal of segments II, III and IV for localized Caroli's disease with multiple intrahepatic calculi. The second patient underwent resection of segment II and III with Roux-en-Y hepaticojejunostomy for right and left intrahepatic calculi with an abscess in the left lobe of the liver and a choledochal cyst.

Metastatic amelanotic melanoma.

We report a 60 year-old-man who presented with generalized abdominal colicky pain. He had a history of left great toe dysarticulation done for amelanotic melanoma one year ago. Investigations were suggestive of metastases of melanoma to the small intestine. Exploratory laparotomy with segmental ileal resection and anastomosis was performed. Histological examination showed features of amelanotic melanoma characterized by absence of melanin pigment.

Massive lower intestinal bleeding--a decade of experience.

BACKGROUND: Lower gastrointestinal bleeding is defined as hemorrhage orginating distal to the ligament of Treitz. Its diagnosis is difficult, often requiring endoscopy, angiography and isotope scans. METHODS: All patients with massive lower gastrointestinal bleeding seen in three gastroenterology centers of Armed Forces during an 11 year period between 1988 and 1999 were retrospectively analysed. RESULTS: A total of 91 patients with massive lower gastro intestinal bleeding were seen during 11 years. The mean age of the patients was 38.9 years and 64 were males. Aetiological diagnosis was: Non-specific ulcers--11, Ileal tuberculosis--8, NSAID enteropathy--8, Enteric fever--7, Meckel's diverticulum--7, Polyps--6, Ulcerative colitis--5, Carcinoma colon--5, Colonic diverticulosis--5, No cause found--5, Polyposis coli--5, Jejunal diverticulae--3, Angiodysplasia colon--3, Radiation colitis--3, Ischaemic colitis--3, Ileal tumor--2, Ileal angiodysplasia--2, Intestinal Lymphoma--2, Bechet's syndrome--1. Bleeding stopped on conservative therapy in 18 patients (including 5 where no diagnosis could be made). Diagnosis was made in 36 patients on fiber-optic colonoscopy done during active bleeding. Remaining patients were subjected to emergency laparotomy and diagnosis was obvious on inspection of abdominal contents in 25 cases. The diagnosis was finally made in remaining 12 cases by intraoperative endoscopic examination through an ileotomy. Four patients died, only one of them due to rebleed after surgery from an additional lesion. CONCLUSIONS: Compared with experience in Western countries, massive lower gastro-intestinal hemorrhage in India affects younger patients, has different causes and carries a lower mortality. Colonoscopy is useful in making diagnosis during active lower intestinal bleeding in about one-third cases. Exploratory laparotomy and Intra-operative endoscopy are complimentary to above examination and can make the diagnosis in most of the remaining cases.

Microbial metabolism as an evolutionary response: the cybernetic approach to modeling.

The growth and metabolic capabilities of microorganisms depend on their interactions with the culture medium. Many media contain two or more key substrates, and an organism may have different preferences for the components. Microorganisms adjust their preferences according to the prevailing conditions so as to favor their own survival. Cybernetic modeling describes this evolutionary strategy by defining a goal that an organism tries to attain optimally at all times. The goal is often, but not always, maximization of growth, and it may require the cells to manipulate their metabolic processes in response to changing environmental conditions. The cybernetic approach overcomes some of the limitations of metabolic control analysis (MCA), but it does not substitute MCA. Here we review the development of the cybernetic modeling of microbial metabolism, how it may be combined with MCA, and what improvements are needed to make it a viable technique for industrial fermentation processes.

Efficacy of hydrolytic enzymes in preventing radiation therapy-induced side effects in patients with head and neck cancers.

PURPOSE: Based on in vitro and on clinical evidence of protection against acute side effects of radiation, a prospective randomized, open study was performed to determine the efficacy of an oral proteolytic enzyme preparation in patients with head and neck cancer receiving conventional fractionated radiation therapy. METHODS: Patients with stage T3/T4 head and neck cancer were eligible. One hundred patients from two centres were entered into the study. 60Co gamma-radiation was delivered at a standard daily radiation dose of 2 Gy in 25-35 fractions over a period of 6-7 weeks. Two lateral parallel opposing fields were used with a portal area of 10 x 15 cm. Patients assigned to the test group arm additionally received enzyme tablets orally t.i.d. starting 3 days prior to radiation therapy, and continuing up to 5 days after completion of the course of radiation therapy. Patients in the control arm were not given any drug or placebo. Acute radiation side effects were described as mucositis, skin reaction, dysphagia, and were graded at each visit during and after radiation therapy, following RTOG/EORTC criteria. RESULTS: The severity (maximum extent) of acute radiation therapy side effects was significantly less in enzyme-treated patients than in control patients: mucositis (mean: 1.3 vs 2.2, P < 0.001), skin reaction (1.2 vs 2.4, P < 0.001) and dysphagia (1.4 vs 2.2, P < 0.001). The duration of these side effects as well as the sum scores of side effects were also less in the study arm. CONCLUSIONS: Combination of enzyme therapy with conventional fractionated radiation therapy was feasible and well-tolerated. There was significant protection against acute side effects of radiation therapy in the study arm. Not only was the severity of acute side effects less but the duration was shorter and the time to onset was also delayed. Prospective randomized double-blind studies would verify this role of an oral enzyme therapy as standard co-medication with radiation therapy to the head and neck region.

Kinetics of phthalate reactions with ammonium hydroxide in aqueous matrix.

Common phthalate pollutants, such as dimethyl phthalate and diethyl phthalate found in aqueous environmental matrices react with ammonium hydroxide at ordinary temperatures exhibiting an overall reaction order in the range 1.3-1.4. While the reaction is of first order with respect to the phthalate, the order of reaction is fractional in ammonium hydroxide. The rate constants for the reactions of these two phthalates in alkaline waters at ambient temperatures are in the range 1.3 x 10(-4) and 8.5 x 10(-5) Lx/mol s. Under these conditions the estimated half-lives for dimethyl phthalate and diethyl phthalate at a concentration of each at 20 mg/L is 4.5 and 14 h, respectively. Other phthalates are expected to exhibit similar kinetics in their base hydrolysis with NH4OH. Thus, the presence of both the phthalate esters and ammonia or ammonium salts in the water under alkaline conditions may result in their self-removal by hydrolysis.

Penicillin fermentation: mechanisms and models for industrial-scale bioreactors.

Even after many years of research and industrial practice, the production of penicillin G in fed-batch fermentation by Penicillium crysogenum continues to attract research interest. There are many reasons: the commercial and therapeutic importance of penicillin and its derivatives, the complexity of cell growth, and the impact of engineering variables, the last of which are significant in large bioreactors but are not yet fully understood. Extensive research has generated new information on the mechanisms of cellular reactions and morphological features of the mycelia and their role in the synthesis of the product. Given a choice of mechanisms, models of different degrees of complexity, for both cellular differentiation and bioreactor performance, have been proposed. The more complex models require and provide more information. They are also more difficult to evaluate and apply in automatic control systems for production-scale bioreactors. The present review considers the evolution of recent knowledge and models from this perspective.

HARTMANN'S PROCEDURE REVISITED.

Between July 1991 and June 1999 out of 176 patients undergoing colonic surgery (elective and emergency), Hartmann's procedure was performed in 63. There were 39 males and 24 females. Mean age was 43 years (range 12 to 81). To assess the utility of Hartmann's procedure the documents of all these 63 patients were retrospectively analysed. In 47 bowel continuity was reestablished. The over all mortality in first stage operation (Hartmann's procedure) was 12.7% and mortality in the second stage procedure (reestablishing bowel continuity) was nil. Complication rate was drastically less in second operation. The authors conclude that Hartmann's procedure is safe and effective while dealing with colorectal pathologies as resection and primary anastomosis is fraught with danger.

Plasmodium chabaudi-infected erythrocytes adhere to CD36 and bind to microvascular endothelial cells in an organ-specific way.

Adherence of erythrocytes infected with Plasmodium falciparum to microvascular endothelial cells (sequestration) is considered to play an important role in parasite virulence and pathogenesis. However, the real importance of sequestration for infection and disease has never been fully assessed. The absence of an appropriate in vivo model for sequestration has been a major barrier. We have examined the rodent malaria parasite Plasmodium chabaudi chabaudi AS in mice as a potential model. Erythrocytes infected with this parasite adhere in vitro to purified CD36, a critical endothelium receptor for binding P. falciparum-infected erythrocytes. P. c. chabaudi-infected erythrocytes adhere in vitro to endothelial cells in a gamma interferon-dependent manner, suggesting the involvement of additional adhesion molecules in the binding process, as is also the case with P. falciparum-infected cells. Furthermore, plasma or sera from infected and hyperimmune mice, respectively, have the ability to block binding of infected erythrocytes to endothelial cells. In vivo, erythrocytes containing mature P. c. chabaudi parasites are sequestered from the peripheral circulation. Sequestration is organ specific, occurring primarily in the liver, although intimate contact between infected erythrocytes and endothelial cells is also observed in the spleen and brain. The results are discussed in the context of the use of this model to study (i) the relationship between endothelial cell activation and the level of sequestration and (ii) the primary function of sequestration in malaria infection.