Effect of air pollution on peak expiratory flow rate variability.

Exposure to air pollution affects pulmonary functions adversely. Effect of exposure to pollution on diurnal variation of peak flow was assessed in healthy students. Three hundred healthy age-matched nonsmoker students were studied. They were categorized into two groups on the basis of their residence: commuters and living on campus. Peak expiratory flow (PEF) recordings were made twice daily for 2 days with the Pink City Flow Meter. The measurement was then used to calculate for each subject the amplitude percentage mean, which is an index for expressing PEF variability for epidemiological purposes (Higgins BG, Britton JR, Chinns Jones TD, Jenkinson D, Burnery PG, Tattersfield AE. Distribution of peak expiratory flow variability in a population sample. Am Rev Respir Dis 1989; 140:1368-1372). Air pollution parameters were quantified by measurement of sulfur dioxide (SO2), oxides of nitrogen (NO2), carbon monoxide (CO), and respirable suspended particulate matter (RSPM) in the ambient air at the campus and on the roadside. The mean values of PEF variability (amplitude percent mean) in the students living on campus and in the commuters were 5.7 +/- 3.2 and 11 +/- 3.6, respectively (P < .05). Among the commuters, maximum number of subjects showed amplitude percentage mean PEFR at the higher end of variability distribution, as compared to the students living on campus, among whom the majority of subjects fell in the lower ranges of variability distribution. The ambient air quality parameters, namely SO2, NO2, CO, and RSPM were significantly lower on the campus. It can be concluded that long-term periodic exposure to air pollution can lead to increased PEF variability even in healthy subjects. Measurement of PEF variability may prove to be a simple test to measure effect of air pollution in healthy subjects.     

Computed tomography of the abdomen with fat density oral contrast medium.

A 12.5% corn oil-emulsion (COE) was tested as an oral contrast agent for abdominal computed tomography (CT) examinations in 100 patients. The results were compared with those obtained from another group of patients who received a conventional, high-density, oral contrast agent (2-3% iodinated solution). There was no statistically significant difference in the subjects' tolerance to the two agents (P greater than 0.05). There was, however, a significant improvement in image quality with COE (P less than 0.05). Gastrointestinal tract discrimination, and mucosal and mural visualisation was of higher quality with fat density oral contrast medium than with the high-density contrast agent. These data suggest that COE should be considered for routine use as an alternative to conventional high density oral contrast agents in upper abdominal CT.     

Presence and measurement oftele-methylhistamine in mast cells

The histamine metabolitetele-methylhistamine (t-MH) was identified and measured in crude and purified peritoneal mast cells (MCs). Peritoneal dialysates, peritoneal cells, and purified MCs all containedt-MH in concentrations representing about 0.2% of the corresponding histamine (HA) levels.T-MH levels in crude cells represented about 70% of the total dialysate levels, indicating the presence of extracellular as well as intracellulart-MH.T-MH levels per MC in purified fractions were similar to those of crude fractions, indicating a MC origin for the intracellulart-MH. Histamine methyltransferase activity was not detected in crude or purified MC fractions, and incubations with the monoamine oxidase inhibitor pargyline failed to increase the content or release oft-MH in either fraction, suggesting a very slow or non-existent histamine methylation in MCs. Compound 48/80 produced a temperature-dependent release of HA andt-MH in crude and purified preparations, and Triton X-100 also released both amines. In all cases, the degree of release of both amines was correlated, consistent with a granular origin fort-MH in MCs. The low concentrations oft-MH in MCs do not necessarily indicate a role for MCs in HA metabolism, but suggest thatt-MH may be a valuable marker for non-MC HA.     

The successful use of alemtuzumab for treatment of steroid‐refractory acute graft‐versus‐host disease in pediatric patients

SR‐aGVHD remains a significant cause of morbidity and mortality in allogeneic HCT recipients. Alemtuzumab has been used with success in adult patients but has not been studied in the pediatric setting. To estimate the effectiveness of alemtuzumab for the treatment of SR‐aGVHD in pediatric patients, we retrospectively reviewed the charts of 19 patients (median age 4 yr, range 0.5–28 years) with grades II (n = 3), III (n = 10), or IV (n = 6) SR‐aGVHD who received alemtuzumab treatment. Patients received a median dose of 0.9 mg/kg alemtuzumab (range 0.3–2 mg/kg) divided over 2–6 days. Eighty‐nine percent of patients received additional courses. A complete response, defined as GVHD of grade 0 at four wk following the first alemtuzumab course, was observed in nine patients (47%). A partial response, defined as an improvement in grade after four wk, was observed in five patients (26%). There was no response in five patients (26%). The overall response rate at four wk was 73%. Infectious complications included bacteremia (47%), presumed or documented fungal infections (21%), adenovirus viremia (52%), EBV viremia (36%), and CMV viremia (36%). We conclude that alemtuzumab is effective for SR‐aGVHD in pediatric patients with a tolerable spectrum of complications.     

Evidence of depot‐specific regulation of all‐trans‐retinoic acid biosynthesis in human adipose tissue

The prevalence of obesity continues to rise, underscoring the need to better understand the pathways mediating adipose tissue (AT) expansion. All‐trans‐retinoic acid (atRA), a bioactive vitamin A metabolite, regulates adipogenesis and energy metabolism, and, in rodent studies, aberrant vitamin A metabolism appears a key facet of metabolic dysregulation. The relevance of these findings to human disease is unknown, as are the specific enzymes implicated in vitamin A metabolism within human AT. We hypothesized that in human AT, family 1A aldehyde dehydrogenase (ALDH1A) enzymes contribute to atRA biosynthesis in a depot‐specific manner. To test this hypothesis, parallel samples of subcutaneous and omental AT from participants (n = 15) were collected during elective abdominal surgeries to quantify atRA biosynthesis and key atRA synthesizing enzymes. ALDH1A1 was the most abundant ALDH1A isoform in both AT depots with expression approximately twofold higher in omental than subcutaneous AT. ALDH1A2 was detected only in omental AT. Formation velocity of atRA was approximately threefold higher (p = 0.0001) in omental AT (9.8 [7.6, 11.2]) pmol/min/mg) than subcutaneous AT (3.2 [2.1, 4.0] pmol/min/mg) and correlated with ALDH1A2 expression in omental AT (β‐coefficient = 3.07, p = 0.0007) and with ALDH1A1 expression in subcutaneous AT (β‐coefficient = 0.13, p = 0.003). Despite a positive correlation between body mass index (BMI) and omental ALDH1A1 protein expression (Spearman r = 0.65, p = 0.01), BMI did not correlate with atRA formation. Our findings suggest that ALDH1A2 is the primary mediator of atRA formation in omental AT, whereas ALDH1A1 is the principal atRA‐synthesizing enzyme in subcutaneous AT. These data highlight AT depot as a critical variable for defining the roles of retinoids in human AT biology.

Study Highlights

• WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

Rodent data suggest that dysregulated production of all‐trans‐retinoic acid (atRA), the primary bioactive metabolite of vitamin A, may contribute to body weight gain and its complications. However, the key enzymes responsible for atRA biosynthesis in human adipose tissue have not been identified, nor has the relationship between body weight and adipose tissue atRA biosynthesis been evaluated in humans.

• WHAT QUESTION DID THIS STUDY ADDRESS?

This study sought to identify the key enzymes involved in atRA biosynthesis in human omental and subcutaneous adipose tissue. This study also quantified atRA formation velocity and explored the potential relationship between body mass index (BMI) and atRA biosynthesis in both adipose tissue depots.

• WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

This study establishes that among the aldehyde dehydrogenase (ALDH) isoforms, ALDH1A1 and ALDH1A2 both contribute to atRA biosynthesis in human omental adipose tissue, whereas only ALDH1A1 contributes to atRA biosynthesis in subcutaneous adipose tissue. Both ALDH1A1 expression and atRA formation velocity are substantially higher in omental than subcutaneous adipose tissue. Omental ALDH1A1 protein expression exhibits a positive correlation with BMI, but atRA formation velocity in both omental and subcutaneous adipose tissue shows no correlation with BMI. Thus, these findings highlight discrepancies between human and rodent adipose tissue biology and, moreover, reveal depot‐specific regulation of vitamin A metabolism in human adipose tissue.

• HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?

This line of research ultimately is intended to define the roles of vitamin A metabolites in the regulation of tissue remodeling and energy partitioning in human adipose tissue. This knowledge could contribute to the delineation of mechanisms underlying progressive obesity and its complications.     

Male infertility microsurgical training

A strong foundation in microsurgical techniques is imperative for urologists and clinical andrologists specializing in male infertility. Laboratory-based microsurgical training enhances surgical skills, improves surgeon confidence, and reduces stress and operating time, thereby benefiting both the patient and the surgeon. The laboratory environment additionally allows for the development of novel and innovative techniques. This review provides guidelines for setting up a microsurgical laboratory to develop and enhance microsurgical skills using synthetic and animal models.     

Pseudolipoma of the Inferior Vena Cava

Pseudolipoma of inferior vena cava refers to a normal variant of adipose collection that is seen in typical pericaval or juxtacaval location; however, it mimics an intracaval mass lesion, especially fat-containing lesions such as lipoma. Awareness of this entity is very important to avoid misdiagnosis and unnecessary diagnostic procedures.