Engaged Environmental Science for Underserved Youth

The National Institute for Environmental Health Sciences has called for targeted efforts to engage underserved youth in environmental education programs that support environmental literacy and contribute to the development of a diverse workforce pipeline for environmental science-related occupations. Evidence suggests that career knowledge among low income and minority youth is more likely to be incompatible with post-secondary educational opportunities than other racial and ethnic groups. One approach to attenuating discordant college and career expectations among underserved youth is building networks for information sharing between secondary and post-secondary students. The purpose of this commentary is to describe the development and implementation of a high school curriculum on environmental science and environmental justice by Texas A&M University in collaboration with community engagement partners, students, and teachers at Furr High School, an innovative XQ Super School in Houston, Texas.

Fish oil (n-3) polyunsaturated fatty acids beneficially affect biliary cholesterol nucleation time in obese women losing weight

It has been reported that intake of (n-3) polyunsaturated fatty acids (PUFA) reduces the risk of coronary heart disease and decreases biliary cholesterol saturation in the bile of gallstone patients. We investigated the effect of n-3 PUFA on cholesterol saturation index (CSI) and nucleation time (NT) in obese subjects who were losing weight. This was a double-blind, placebo-controlled clinical trial. Obese women (n = 35) with a body mass index (BMI) > or = 30 kg/m(2), with no prior history of gallstones or cholecystectomy by ultrasound were first studied to ensure absence of stones or biliary sludge. The women were then assigned to a hypocaloric regimen [5.02 MJ (1200 kcal)/d] and to receive 1200 mg/d of ursodeoxycholic acid (UDCA), 11.3 g/d of (n-3) PUFA or a placebo for 6 wk. BMI, CSI and NT were recorded at baseline and at the end of the experimental period. BMI decreased 5.75 +/- 2.7%/mo (range, 1.5-12.42%/mo) during the experiment. The CSI did not change in any of the groups. Cholesterol NT decreased significantly in the UDCA and placebo groups, but not in the (n-3) PUFA group. None of the women had developed gallstones at 6 wk. These results suggest that (n-3) PUFA maintain the CSI and NT in obese women during rapid weight loss, which probably results in the prevention of cholesterol gallstone formation.

Management of choledocholithiasis found during laparoscopic cholecystectomy: a strategy based on the use of postoperative endoscopic retrograde cholangiography and sphincterotomy

BACKGROUND

Several strategies have been proposed for the diagnosis and management of common bile duct stones in candidates for laparoscopic cholecystectomy.

METHODS

Clinical characteristics, treatment, and outcome of five patients in whom CBDS were demonstrated by intraoperative cholangiography during a laparoscopic cholecystectomy were analyzed. All patients were treated by endoscopic sphincterotomy. Post-treatment outcome was emphasized.

RESULTS

Mean age of the patients was 55 years. Four were female and one male. Preoperative liver function tests were within normal range in all patients. Duct stones of a mean size of 0.8 cm were found in the lower third of the biliary tree. Four were retrieved by endoscopic sphincteroplasty using a Dormia basket and in one patient after an unsuccessful endoscopic attempt, an open choledochoduodenostomy was performed. There were no post-treatment complications. At a mean follow-up of 2 years no evidence of recurrent common bile duct obstruction has been found in any patient.

CONCLUSIONS

This small series supports the use of postoperative endoscopic retrograde cholangiography and sphincteroplasty in patients with unsuspected common bile duct stones found during laparoscopic cholecystectomy. Retrieval of the stones immediately after surgery at the operative room is recommended.

Interleukin-4-deficient BALB/c mice develop an enhanced Th1-like response but control cardiac inflammation following Borrelia burgdorferi infection

Interleukin-4 has been reported to critically modulate Borrelia burgdorferi infection and Lyme arthritis in experimental murine models. To determine the in vivo role of IL-4 in controlling Lyme carditis, we compared immunological responses and the severity of cardiac inflammation in wild-type BALB/c (IL-4 +/+) and IL-4 deficient BALB/c (IL-4 -/-) mice infected with B. burgdorferi by tick-bite. At day 15 and 30 post-infection IL-4 -/- mice produced significantly greater titers of spirochete-specific IgG2a than the wild-type IL-4 +/+ mice, which produced significantly more spirochete-specific IgG1. Following in vitro antigenic stimulation with B. burgdorferi antigen, splenocytes from infected IL-4 -/- and IL-4 +/+ mice displayed similar magnitudes of proliferative responses at day 15 and 30 post-infection. At day 30 antigen-stimulated splenocytes from infected IL-4 -/- mice, however, produced significantly more IFN-gamma than those derived from similarly infected IL-4 +/+ mice, suggesting that Th1-influenced responses predominated in IL-4 -/- mice. Moreover, inflamed hearts from IL-4 -/- mice displayed higher levels of IFN-gamma and TNF-alpha transcripts as compared to IL-4 +/+ mice. At both time points antigen-stimulated splenocytes from IL-4 +/+ and IL-4 -/- mice produced significant amounts of IL-10 but those from IL-4 +/+ mice produced either no or little IL-4. Histopathology demonstrated typical Lyme carditis in both IL-4 +/+ and IL-4 -/- mice at day 15 and day 30. Although Borrelia-infected IL-4 -/- mice developed a more severe carditis on day 30, the carditis resolved by day 50, as it did in IL4 +/+ mice. These results indicate that although IL-4 may help limit the severity of Lyme carditis, its absence does not preclude resolution of cardiac lesions.

Geographic differences in bone mineral density of Mexican women

The aim of this study was to generate standard curves for normal spinal and femoral neck bone mineral density (BMD) in Mexican women using dual-energy X-ray absorptiometry (DXA), to analyze geographic differences and to compare these with 'Hispanic' reference data to determine its applicability. This was a cross-sectional study of 4460 urban, clinically normal, Mexican women, aged 20-90 years, from 10 different cities in Mexico (5 in the north, 4 in the center and 1 in the southeast) with densitometry centers. Women with suspected medical conditions or who had used drugs affecting bone metabolism, were excluded. Lumbar spine BMD was significantly higher (1.089 +/- 0.18 g/cm2) in women from the northern part of Mexico, with intermediate values in the center (1.065 +/- 0.17 g/cm2) and lower values (1.013 +/- 0.19 g/cm2) in the southeast (p < 0.0001). Similarly, femoral neck BMD was significantly higher in women from the north (0.895 +/- 0.14 g/cm2), intermediate in the center (0.864 +/- 0.14 g/cm2) and lower (0.844 +/- 0.14 g/cm ) in the southeast part of Mexico (p < 0.0001). Northern Mexican women tend to be taller and heavier than women from the center and, even more, than those from the southeast of Mexico (p < 0.0001). However, these differences in BMD remained significant after adjustment for weight (p < 0.0001). A significant loss (p < 0.0001) in BMD was observed from 40 to 69 years of age at the lumbar spine and up to the eighth decade at the femoral neck. Higher and lower lumbar spine values, as compared with the 'Hispanic' population, were observed in Mexican mestizo women from the northern and southeastern regions, respectively. In conclusion, there are geographic differences in weight and height of Mexican women, and in BMD despite adjustment for weight.

[Osteoporosis in Mexican postmenopausal women. Magnitude of the problem. Multicenter study]

Incidencia of osteoporosis induced fractures increases with age; risk increases exponentially as bone mass decreases. Women are prone to osteoporosis 2 to 3 times more than men, due to lower "peak" bone mass and the accelerated loss that occurs after the menopause. The prevalence of osteoporosis in with Caucasian postmenopausal women varies from 16 to 30% depending upon the number of sites measured (lumbar spine/hip and/or forearm). The aim of this study was to estimate the prevalence of osteopenia and osteoporosis in pre and postmenopausal Mexican women in relation to men, and to that reported in Caucasia women. The study involved 4,821 apparently healthy subjects (without known risk factors for osteoporosis), 4,467 females and 354 males from 11 different centers of Mexican Republic, 20 to 90 years old, using DXA bone densitometry of lumbar spine and hip. Prevalence of osteoporosis in women is twice that in men (P < 0.001), and it increases with age, particularly after the menopause (P < 0.0001). Our study found a prevalence of osteoporosis of the lumbar spine and/or hip in apparently healthy postmenopausal Mexican women over 50 years of age of 16%, increasing to 20% in those women with or without risk factors who attended voluntarily or by suggestion of their physician to be studied. The prevalence values obtained seem to be lower than those reported for Caucasian women, 30%. We found a prevalence of osteoporosis of 16% and of osteopenia of 57% in women 50 years of age and older. We also found a higher prevalence of osteoporosis in women of the south east part of the county.

Practical guidelines for developing a hospital-based wound and ostomy clinic

Multidisciplinary teams save time and money while improving quality of patient care. Hospital-based wound/ostomy clinics provide patients with holistic, one-stop, expert care with access to a variety of diagnostic and treatment modalities. The authors discuss how to assemble all the ingredients for a successful multidisciplinary hospital-based clinic, how to make it work, and how to measure its cost-effectiveness for patient, hospital, community and nation. The original model clinic established in Costa Rica using these methods was so successful at providing efficient, high quality, cost-effective care that it has been adopted in 17 different locations there, and similar clinics are being developed in other countries. This model is applicable to industrialized and developing countries. By focusing hospital resources on evidence-based wound/ostomy care, it has the potential to revolutionize wound and ostomy care around the world.

Plasma-cell tumours of the condyle

Plasma cell tumours are a group of disorders which are characterized by neoplastic proliferation of atypical plasma cells involved in the production of monoclonal immunoglobulins. Bone pain, renal insufficiency and normocytic-normochromic anaemia are suggestive data for diagnosis. In 12-15% of cases of multiple myeloma, the first manifestation of the disease appears in the jaw bones and oral cavity. Two cases of multiple myeloma affecting the mandibular condyle are presented, and the incidence of oral and maxillofacial lesions is briefly reviewed.

[The recurrence of duodenal ulcer in patients undergoing treatment with ranitidine and placebo. A multicenter study]

This randomised, double-blind multicenter study was conducted in order to evaluate the long-term effect (one year) of 150 mg ranitidine vs placebo in 51 patients with healed duodenal ulcer. Seventeen patients had ulcer recurrence at the end of follow-up, one among the 24 patients that received ranitidine and 16 among the 27 patients that received placebo (p = 0.00009). No side effects was detected. Our results support the usefulness of a one-year maintenance therapy with 150 mg ranitidine.

[Changes in arterial oxygen saturation in patients undergoing endoscopy of the upper digestive tract]

This study showed how often oxygen desaturation occurred in patients undergoing upper endoscopy procedures; extent of desaturation after sedation with diazepam, relationship between desaturation and respiratory function status and compared two types of instruments Olympus (XQ, K10). Ninety nine patients undergoing elective and emergency upper endoscopy procedures were monitorized with pulse oximeter before sedation, during and after the procedure. We did not find any change clinically significant.

[Sphincteroplasty of the minor papilla in a female patient with pancreas divisum]

We report the case of a 30 year old woman with recurrent episodes of acute pancreatitis secondary to pancreas divisum. The diagnosis was established 18 years after the initiation of her symptomatology. She denied a family history of pancreatic disease and had no risk factors in her personal history. Diagnosis was confirmed by endoscopic retrograde cholangiopancreatography. She was surgically treated by means of a sphincteroplasty of the minor papillae with excellent results. After three years of follow-up, the patient remains asymptomatic.

[Elective endoscopic sclerotherapy in esophageal varices]

We present our experience with elective sclerotherapy in ten years. 64 male and 57 females, median age 52.5 years, were treated. Post-necrosis cirrhosis was the primordial etiology in 44% followed by alcoholic in 40%. In regards to Child classification, 51% were "C"; 24% "B" and 25% "A". With variceal eradication we found no rebleeding, but in those without changes in variceal size, it was 82%. At six months, control of variceal hemorrhage was respectively to groups A, B, and C. 86%, 71% and 63%. The control at long follow-up were respectively 74%, 68% & 57%. Survival was directly related to the level of hepatic function instead of sclerosis. Complications were 2 to be 3% being the most severe: pleural effusion; mediastinitis and fiber. Mortality was 0.8% in one patient with esophageal perforation.

[Endoscopic pancreatography]

A review was done on the Endoscopic Pancreatography as a method of diagnosis. Emphasis was made on the historical and technical aspects, indications, contraindications, limitations and complications of the method. Also, we reported our experience about Endoscopic Pancreatography.

[Retrospective evaluation of 500 endoscopic cholangiopancreatographies performed at the Instituto Nacional de la Nutrición "Salvador Zubiran"]

We evaluated 500 endoscopic retrograde cholangiopancreatographies (ERCP) performed on 422 patients during a 5-year period in the Gastrointestinal Endoscopy Department, Instituto Nacional de la Nutrición Salvador Zubirán, México, D.F. ERCP combines endoscopic and radiologic techniques in order to obtain high quality opacification of pancreatic and biliary ducts. The rate of success for cannulation was 90%; desired duct opacification was possible in 89%. The most frequent indication for ERCP was to establish the differential diagnosis for jaundice; biliary stones in the common bile duct was the most frequent diagnosis, followed by normal biliary ducts. Pancreatography was normal in 74% of patients. ERCP complications were detected in 5.6%; fever and transient pain was the most common complaint in 1.6%. Mortality attributable to the procedure was 0.8%. From histological corroboration of cases by surgery or postmortem studies, diagnostic sensitivity was 92%, specificity 76%, positive predictive value 96% and a prevalence of 89%. We conclude that ERCP is highly sensitive and specific in diagnosing bilio-pancreatic-duodenal disease. Our results are comparable to other's experiences published throughout the world.

Production of monovalent anti-Bothrops asper antivenom: development of immune response in horses and neutralizing ability

A monovalent antivenom was produced by immunizing two horses with venom of the pit viper Bothrops asper (Ophidia: Viperidae). Although development of the immune response against four toxic and enzymatic activities of the venom was similar in both horses during the first two thirds of the immunization schedule, antibody response in one of the horses reached much higher levels in the last part of the immunization. Immunoelectrophoretic analysis indicates that there were precipitating antibodies in the sera of these horses during all the stages of immunization. However, immunoprecipitation did not correlate with the ability of sera to neutralize toxic activities of B. asper venom. Monovalent antivenom was more effective than the commercially available polyvalent antivenom in the neutralization of Bothrops asper venom. On the other hand, despite the fact that it neutralizes lethal and hemorrhagic activities of the venoms of Lachesia muta and Crotalus durissus durissus, it was less effective than polyvalent antivenom in these neutralizations. Moreover, it does not neutralize defibrinating activity induced by these two venoms, whereas it neutralizes this effect in the case of B. asper venom. It is proposed that monovalent antivenom may be highly effective in the case of envenomations induced by Bothrops asper venom; its use in treating accidents by L. muta and C. durissus would be indicated only if polyvalent antivenom is not available. Results also demonstrate that it is important to monitor antibody response individually in horses being immunized for antivenom production, due to the conspicuous variability in the response of different animals.

Endoscopic placement of enteral feeding tubes

The techniques for placement of feeding tubes using fiberscopes are described and an evaluation of the results obtained in the last 12 months is made. The techniques are discussed and compared with other methods of enteral feeding known at present. It is concluded that placement of feeding tubes by endoscopy can be achieved easily, that it is possible to choose the site of enteric liberation of nutrients under conditions which previously represented contraindications, and that this procedure is free of complications even during long periods of time.

A glucose-6-phosphate dehydrogenase variant, Gd(-) Santamaria found in Costa Rica

Red cell glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-chromosomal-linked abnormality often associated with hemolytic anemia. The G6PD variants obtained from 2 unrelated males, one associated with enzyme deficiency and history of hemolytic jaundice, and the other associated with enzyme deficiency but no hemolytic problems, were examined. Although the 2 subjects have no known consanguinity, the two enzymes could not be distinguished from each other in respect to their electrophoretic mobilities and kinetic properties, both exhibiting slower than normal anodal electrophoretic mobility, lower Km for G6P and NADP and higher rate of utilization of 2-deoxy-G6P and deamino-NADP. An unique double-banded pattern was observed in starch gel electrophoresis at pH 7.0 and pH 8.6. The variant is distinguished from all reported Gd variants, and it is designated Gd(-) Santamaria.

G6PD-Puerto Limón: a new deficient variant of glucose-6-phosphate dehydrogenase associated with congenital nonspherocytic hemolytic anemia

A new glucose-6-phosphate dehydrogenase (G6PD) variant with total deficiency associated with congenital nonspherocytic hemolytic anemia was found in a Costa Rican family. The study of the partially purified enzyme revealed thermal instability, increased G6P affinity, abnormal pH optimum, increased utilization of analogues, and a chromatographic behavior that differs from all the variants previously described. Thus, this new variant was designated G6PD Puerto Limón.

Survival and quality of life after selective portasystemic shunts

Selective portasystemic shunts were performed in 55 consecutive patients; 27 underwent end-to-end selective renosplenic shunt, 18 distal splenorenal shunt and 10 splenocaval shunt. Thirty-one patients were in Child's class A, 18 were in class B and 6 in class C. Hospital mortality for the whole group was 16 percent and occurred less frequently in class A than in class B and C patients. Five year predicted survival for the whole group was 59 percent. At the same period of follow-up, class A patients had a higher survival rate than those in class B and C (83 percent versus 36 percent; p < 0.01). No striking difference in 5 year survival was evident in alcoholics and nonalcoholics (52 percent versus 61 percent). After surgery, long-term portasystemic encephalopathy and bleeding were noted in 2 of 36 survivors. For class A patients, selective portal shunts offer an adequate and relative safe method for decreasing mortality due to variceal bleeding.

[Rare hemoglobinopathies in Costa Rica]

Among the rare hemoglobinopathies found in Cost Rica are those of the Alfa, Beta, and Delta chains. Among these, Hb Cubujuquí, an undescribed variant, is of special interest. There was an association between the different thalassemic syndromes and their combinations with abnormal hemoglobins.

[Meso-renal derivation. A surgical alternative in the treatment of portal hypertension]

Meso-renal shunt (MRS) has been designed for patients with biliary cirrhosis and portal hypertension, in whom the derivation of the portal flow must be done prior to the biliary surgery. We performed the MRS in five patients. In three due to secondary biliary cirrhosis, one case due to criptogenic cirrhosis and the last presenting cavernomatous degeneration of the portal vein. After the MRS one patient died 33 days later due to acute liver failure and hepatorenal syndrome. Of the survivors three are enjoying normal lifestyle, one of them was underwent colecistectomy and coledocostomy without any surgical problems. One patient was lost to follow up out presenting at that time chronic porta-systemic encephalopathy. When necessary the MRS may offer a satisfactory choice, since can be performed far from the subhepatic area, thus allowing to perform further biliary surgery.

Cimetidine in the treatment of duodenal ulcer: double-blind study

To determine the efficacy and safety of cimetidine in the treatment of duodenal ulcer, forty-five patients with this diagnosis were selected for a double-blind study. Diagnosis was confirmed by endoscopy and photography of the lesion. Cimetidine in the form of 200 mg tablets was administered to twenty-four patients at the rate of 1 tablet t.i.d.p.c. and 2 tablets h.s. The same dosage of an identically appearing placebo tablet was given to twenty-one patients. The only other medication permitted was an aluminum + magnesium gel antacid p.r.n. Patients and medication were randomized, the same patients being seen by the same physician throughout the six-week observation period.

Laboratory monitoring of patients (complete blood counts, blood chemistry, urinalysis, gastric acidity) took place at one, two, four and six weeks as did clinical observation.

Three placebo patients withdrew from the study.

The patients on cimetidine showed a statistically significant greater number of healed ulcers, early and late in the treatment; earlier and more persistent pain relief in a greater number; and considerably fewer requiring antacid than those patients on placebo.

No side-effects were noted.

[Surgical treatment of achalasia. Analysis of 27 cases]

1. Esophageal achalasia is a rare disease of unknown origin that occurs with the same frequency in both sexes. 2. During the preoperative workup as well as the postoperative time the following studies should be performed: upper GI series, esophageal manometry and endoscopy with biopsy. 3. In most instances conservative treatment with dilations only provides temporal relief of the symptoms and moreover, is not exempt from complications; it should be employed only in incipient achalasia, in patients who refuse to be operated upon and in those whose general conditions make surgery inadvisable. 4. Surgery can provide a permanent cure for the symptomatology in the majority of the patients, with a very low mortality and morbidity; an operation should be performed early in those who retain more than 10 mls. in the esophagus with persistence of the symptomatology as well as in those patients in whom cancer is suspected. 5. A modified Heller type operation, with abdominal approach with gastrostomy, diaphragmatic hernioplasty and an anti-reflux procedure and when necessary a piloroplasty is the treatment of choice for esophageal achalasia yielding good results in 88.8% of the cases. It should be noted that the degree of postoperative gastroesophageal regurgitation is directly related to the extent to which the gastric incisons is extended below the esophageal-gastric junction.

Chemical characterization of a new haemoglobin variant haemoglobin J Cubujuqui (alpha2141(HC3)Arg replaced by Ser beta2)

Haemoglobin J Cubujuqui (alpha2141(HC3)Arg replaced by Ser beta2) was found during a screening for abnormal haemoglobins carried out in Costa Rica. This variant is clinically silent, although its substitution is in one of the residues involved in the stabilization of the deoxy form of the haemoglobin molecule.