Management of midgut volvulus with extensive necrosis by “patch,drain, and wait” in early infancy and childhood

Midgut volvulus with extensive intestinal necrosis in the newborn period and in early infancy and childhood presents a difficult therapeutic dilemma of how to control sepsis and preserve a maximum and life-sustaining amount of large and small intestine. This problem is similar to that faced in cases of necrotizing enterocolitis with extensive intestinal ischemia and necrosis. The successful use of the patch, drain, and wait approach in necrotizing enterocolitis suggested its potential usefulness in midgut volvulus with similarly extensive necrosis in early life [7]. The basic principles of this approach involve maximum bowel salvage by avoidance of both resection and enterostomy; extensive bilateral Penrose drainage of the peritoneal cavity to provide an exit for sepsis and debris for peritonitis control; and de facto enterostomies for potential enteric fistula capture, gastrostomy for upper gastrointestinal tract venting and decompression, and Broviac catheter placement for long-term hyperalimentation. Three cases involving the successful use of this approach are reported.     

Mutants from V79 fibroblasts exhibiting hypersensitivity to aphidicolin and 3′-azido-3′-deoxythymidine

One variant, aph^hs-3 was previously isolated based on a hypersensitivity to nontoxic concentrations of aphidicolin, a specific inhibitor of DNA polymerases-alpha and delta. This variant was found to be more sensitive to temperatures above 35°C and to 10 µM of 3-azido-3-deoxythymidine (zidovudine, azidothymidine, or AZT) than the parental 743x cells. DNA polymerase activities in the cell extract or in the partially purified fraction by DEAE-cellulose (DE52) anion exchange column from aph^hs-3 were active at 40°C. No significant differences in deoxynucleoside triphosphate pools were observed at 34°C for both the parental 743x and aph^hs-3 cells. Revertants were isolated at 39°C: six revertants (aph^hs-3-tr1 through aph^hs-3-tr6) were obtained without aphidicolin; one revertant aph^hs-3-tar (the tar clone) was selected in aphidicolin (0.12 µM). The hypersensitivity to aphidicolin (Aph^hs) and AZT (AZT^hs) was cosegregated in the revertant aph^hs-3-tr5 (the tr5 clone), while the tar clone was not AZT^hs. There was a similar increase in the specific activity of³H-labeled DNA in all cell lines after additions of [³H]AZT or [³H]thymidine. Additions of purine or pyrimidine arabinosides (araT, araC, and araA) to all cell lines resulted in a similar cytotoxicity, suggesting the anabolism of dTTP was not defective in the tr5 clone. The spontaneous mutation rate at the hypoxanthine-guanine phosphoryltransferase locus using replating techniques and 6-thioguanine resistance selection was 5×10^–7, 2.2×10^–6, or 1.3×10^–6 per generation for the tr5, 743x, or tar cell lines, respectively. Most importantly, DNA polymerase activities in the cell extract of the revertant tr5 clone were inhibited by 0.5 µM AZTTP. In contrast, no inhibition was observed in those of the parental 743x and revertant tar cells. The cosegregation of both Aph^hs and AZT^hs in the tr5 revertant suggests that these two phenotypes may be a result of the same mutational event.     

Autonomic involvement in inherited neuropathies

The inherited peripheral neuropathies constitute a large group of disorders, in some of which the causative metabolic defect has been identified whereas in the majority it is still unknown. Amongst the former, autonomic involvement is an important component in porphyric neuropathy, in the familial amyloid polyneuropathies, in Fabry's disease and in dopamine-hydroxylase deficiency. The latter group includes the hereditary sensory and autonomic neuropathies in some of which, such as the Riley-Day syndrome, autonomic disturbances are prominent, whereas in others they constitute only a minor component of the symptomatology. Autonomic dysfunction is an important component of the neurological manifestations in multiple endocrine neoplasia type IIB.     

CT evidence for the "osseous pinch" mechanism of traumatic aortic injury.

OBJECTIVE. Our prior experiments suggested that traumatic laceration of the aorta induced by rapid deceleration results from pinching of the aorta between the spine and the anterior bony complex (manubrium, clavicle, and first rib). This study examines that hypothesis with in vivo CT data. MATERIALS AND METHODS. In 22 patients with angiographically and surgically proved lacerations of the proximal descending aorta, chest CT scans were obtained before (18) or after (four) surgical repair. The point of impact of the anterior bony complex with the anterior surface of the thoracic spine during compression of the thorax was predicted by simulated rotation of the first rib based on calculations made from the CT scans. RESULTS. In all 22 patients, the projected site of impact of the anterior bony complex with the spine corresponded to the actual injured aortic segment as determined with angiography. CONCLUSION. Our data further support the proposed "osseous pinch" mechanism of injury to explain traumatic tears of the aorta.     

Contribution of thallium-201-SPECT to the grading of tumorous alterations of the brain

Single photon emission computed tomography (SPECT) with thallium-201-chloride (²⁰¹TI) was used in 22 patients to assess the grade of malignancy of brain tumors.Low- and high-grade malignant gliomas could be well differentiated by calculating the Grade Index (GI), i.e., ²⁰¹TI uptake in the tumor area relative to a contralateral brain region. Low-grade gliomas (WHO-grade I–II) usually showed a GI of <1.5. Tumors classified histologically as high-grade malignant (WHO-grade III–IV) had GI values greater than 1.42 and a mean value of 1.89.Until labelled amino-acid tracers for gamma-cameras become commercially available, thallium-201 brain-SPECT can provide an independent and complementary method to CT/MRI for the differential diagnosis of grading of brain tumors. This simple technique can help to reduce sampling errors during needle biopsies of brain tumors, particularly of high-grade lesions incorrectly graded as low-grade tumors due to inadequate biopsy material. In addition, pre- and post-therapy studies can influence the strategy of therapy itself and allow an early detection of recurrences.     

Hypertonic saline lowers raised intracranial pressure in children after head trauma

Eighteen pediatric patients who sustained traumatic brain injury were enrolled in a double-blind, crossover study comparing the effects of 3% saline and 0.9% saline infusions on raised intracranial pressure (ICP). After resuscitation, each patient received a bolus of each saline concentration, and ICP was monitored for 2 h. Initial mean ICP before 0.9% saline infusions equaled 19.3 mm Hg and averaged 20.0 mm Hg during the subsequent 2-h trials (p = 0.32). Baseline mean ICP before 3% saline administration equaled 19.9 mm Hg and averaged 15.8 mm Hg for 2 h postinfusion (p = 0.003). Central venous pressure did not change significantly in either group, nor did measurements of renal function. Serum sodium concentrations increased in all 18 trials of 3% saline. Maximal concentrations of serum sodium occurred 30 min after bolus administration of 3% saline. Three percent saline significantly reduces raised ICP after traumatic brain injury when compared with normal saline. Intravascular dehydration, as measured by central venous pressure, did not occur during the study period.     

A six year longitudinal study of the occupational consequences of drinking over "safe limits" of alcohol.

Although much research has focused on the psychological, social, and economic consequences of heavy problem drinking, there has been far less attention paid to the consequences of "moderate" drinking. This study used a unique opportunity to carry out a six year follow up of a cohort of male and female white collar workers in whom there was baseline information on alcohol consumption and access to details on sickness absence, labour turnover, and promotion. It has provided evidence that even moderate alcohol consumption in the working population is associated with social costs for the employer and the employee, including substantial sickness absence, and lack of promotion in men, although the increase in labour turnover was not statistically significant. The longitudinal examination of consumption in this study suggests that early intervention in a drinking career may reduce alcohol consumption and consequently avoid years of morbidity and sickness absence, as well as having a favourable influence on performance and labour turnover.     

Definition and estimation of lifetime detriment from radiation exposures: principles and methods.

Although the lifetable methodology is a standard tool in epidemiology and risk assessment, there are a number of differences in the way it has been applied by various advisory committees that have attempted to estimate radiation risks. The most fundamental of these differences concerns the choice of parameter to be estimated: the "excess lifetime risk" is the difference in lifetime risks between exposed and unexposed populations; the "risk of exposure-induced death" is the lifetime risk of dying of a disease attributable to exposure. These two quantities are not the same, even at low doses. Although both quantities have some utility in risk assessment, the "risk of exposure-induced death" comes closer to capturing the total impact of exposure. Other differences between reported risk estimates include details of the calculations, the baseline rates and age distributions of the exposed population, the forms of the models for excess rates, handling of organ-specific doses, and the groupings of cancer sites. These issues are discussed theoretically and illustrated with comparisons of the BEIR V and UNSCEAR reports. Although the risk estimates from these two reports are similar for most cancer sites, it is shown that this happens to be the result of an approximate cancellation of a number of differences that could be quite large.     

The importance of employing stringent methods to recruit fertile male controls

Two methods of recruiting fertile male controls were evaluated and compared. The first group was recruited from the partners of women attending an antenatal clinic without obtaining details of their reproductive history. The second group was recruited after obtaining a detailed reproductive history from the couple and employing stringent entry criteria. Entry criteria for the second group included a length of exposure to the risk of pregnancy of not more than 12 months and no previous episode of involuntary infertility for either partner. There were significant differences between the distributions of semen parameters obtained from the two groups, indicating that the selection criteria for "fertile" men significantly influence results obtained and therefore that it is important to employ stringent criteria for the recruitment of fertile male controls. The group which was recruited by stringent criteria (mean length of exposure to the risk of pregnancy of 3 months) was characterised by a significantly higher median concentration of spermatozoa which exhibited slow linear or nonlinear motility. This confirms the findings of a previous study which suggested that slow linear or nonlinear motility are superior forms of spermatozoal motion.     

Selection bias in TEFRA at-risk HMOs

The issue of selection bias was investigated using data from 22 HMOs who are enrolling Medicare beneficiaries under Tax Equity and Fiscal Responsibility Act of 1982 (TEFRA) at-risk contracts. The study differs from previously published analyses of this issue in that it deals with the current Medicare risk program (TEFRA) rather than with earlier Demonstration Programs; as an indicator of selection bias, it utilizes beneficiary functional health status at enrollment; and it examines selection not only at the mean of the health status distribution, but at the two tails (very disabled, very able) as well. For each of the participating HMOs, the functional health status of recent Medicare enrollees was compared with that of a control group of randomly chosen fee-for-service beneficiaries. None of the HMOs experienced adverse selection, whether measured in terms of overall (mean) health status of enrollees or in terms of the proportion of the very disabled population that chose to join. Nine of the 22 HMOs were considered to have experienced favorable selection on the basis of the mean health status of new enrollees. In addition, ten more HMOs were found to have experienced favorable selection in one or both tails of the health status distribution. Although a specific cause for the observed enrollment patterns is not identified, speculation is made on factors that may or may not contribute. Evidence suggests that beneficiary self-selection is probably a more important explanation of these patterns than purposeful actions of HMOs to discourage enrollment by sicker beneficiaries (i.e., "skimming").