Managing High-Altitude Pulmonary Edema with Oxygen Alone: Results of a Randomized Controlled Trial

Yanamandra, Uday, Velu Nair, Surinderpal Singh, Amul Gupta, Deepak Mulajkar, Sushma Yanamandra, Konchok Norgais, Ruchira Mukherjee, Vikrant Singh, Srinivasa A. Bhattachar, Sagarika Patyal, and Rajan Grewal. High-altitude pulmonary edema management: Is anything other than oxygen required? Results of a randomized controlled trial. High Alt Med Biol. 17:294-299, 2016.-Treatment strategies for management of high-altitude pulmonary edema (HAPE) are mainly based on the observational studies with only two randomized controlled trials, thus the practice is very heterogeneous and individualized as per the choice of treating physician. To compare the response to different modalities of therapy in patients with HAPE in a randomized controlled manner. We conducted an open-label, randomized noninferiority trial to compare three modalities of therapy (Therapy 1: supplemental O₂ with oral dexamethasone 8 mg q8 hours [n = 42], Therapy 2: supplemental O₂ with sustained release oral nifedipine 20 mg q8 hours [n = 41], and Therapy 3: only supplemental O₂ [n = 50]). Bed rest was mandated in all patients. The study was conducted in a cohort of previously healthy young lowlander males at an altitude of 3500 m. Baseline characteristics of the patients were comparable in the study arms. Complete response was defined as clinical and radiological resolution of features of HAPE, no oxygen dependency, a normal 6-minute walk test (6MWT) on 2 consecutive days, and normal two-dimensional echocardiography. Results were compared by analysis of variance using SPSS version 16.0. There was no statistical difference in duration of therapy to complete response between the three groups (Therapy 1: 8.1 ± 4.0 days, Therapy 2: 6.7 ± 3.9 days, Therapy 3: 6.8 ± 3.2 days; p = 0.15). There were no deaths in any of the groups. We conclude that oxygen and bed rest alone are adequate therapy for HAPE and that adjuvant pharmacotherapy with either dexamethasone or nifedipine does not hasten recovery.

A case of disseminated superficial porokeratosis associated with giant porokeratosis in pregnancy

A 23-year-old pregnant lady presented with dark raised lesions over face, axillae, and upper limbs of 15-day duration. She was 35 weeks pregnant at the time of onset of the lesions. Dermatological examination revealed hyperpigmented plaques on the face and papules with raised borders in the axillae and proximal arms. Skin biopsy from both the lesions revealed a diagnosis of porokeratosis. She was treated with emollients alone and the lesions regressed four weeks following delivery. This case is being reported for the rare occurrence of the combination of disseminated superficial porokeratosis with giant porokeratosis in pregnancy.

Impact of the HIV epidemic and Anti-Retroviral Treatment policy on lymphoma incidence and subtypes seen in the Western Cape of South Africa, 2002-2009: preliminary findings of the Tygerberg Lymphoma Study Group

The Tygerberg Lymphoma Study Group was constituted in 2007 to quantify the impact of HIV on the pattern and burden of lymphoma cases in the Western Cape of South Africa which currently has an HIV prevalence of 15%. South Africa has had an Anti-Retroviral Treatment (ART) policy and a roll-out plan since 2004 attaining 31% effective coverage in 2009. This study is designed to qualify and establish the impact of HIV epidemic and the ARV roll-out treatment program on the incidence of HIV Related Lymphoma (HRL). Early data document that despite the ART roll out, cases of HRL are increasing in this geographical location, now accounting for 37% of all lymphomas seen in 2009 which is an increase from 5% in 2002. This is in contrast to trends seen in developed environments following the introduction of ART. Also noted are the emergence of subtypes not previously seen in this location such as Burkitt and plasmablastic lymphomas. Burkitt lymphoma is now the commonest HRL seen in this population followed by diffuse large B-cell lymphoma subtypes. The reasons for this observed increase in HRL are not ascribable to improved diagnostic capacity as the tertiary institute in which these diagnoses are made has had significant expertise in this regard for over a decade. We ascribe this paradoxical finding to an ART treatment environment that is ineffective for a diversity of reasons, paramount of which are poor coverage, late commencement of ART and incomplete viral suppression.

Abiotic stress enhances androgenesis from isolated microspores of some legume species (Fabaceae)

To induce androgenesis in field pea, grass pea and the model legume species Medicago truncatula, isolated microspores of various genotypes of these three species were submitted to a range of abiotic stresses prior to and during their initial culture, in order to stimulate them to divide and form embryos. Some stress agents had a positive effect on androgenesis from the treated microspores. Submission of flower buds to a cold period prior to anther excision or microspore isolation, modifying the osmotic pressure of the medium during initial culture and electroporation of isolated microspores were the three major individual stress agents to have an impact on the efficiency of androgenetic proliferation and subsequent differentiation from the microspores of pea, grass pea and M. truncatula genotypes. A combination of osmotic and electric shocks significantly improved responses from isolated microspores and yielded microcalluses and then calluses, but only few underwent morphogenesis. Further work is under way to improve responses and extend them to other genotypes. The results reported here are, to the best of our knowledge, the first successful results from isolated microspores of these species.

A randomized prospective study on the treatment of intra-articular distal radius fractures: open reduction and internal fixation with dorsal plating versus mini open reduction, percutaneous fixation, and external fixation

PURPOSE

To compare 2 methods of surgical treatment for displaced intra-articular fractures of the distal radius: open reduction and internal fixation with dorsal plating (Pi Plate; Synthes, Paoli, PA) versus mini open reduction with percutaneous K-wire and external fixation.

METHODS

Patients with AO type C intra-articular distal radius fractures were randomized into 2 groups: open reduction and internal fixation and dorsal plating or external fixation and K-wires and mini-open reduction. Patients over the age of 70 years with any associated soft-tissue or skeletal injury to the same limb and pre-existing wrist arthrosis or disability were excluded from the study. Objective, subjective, and radiographic outcomes were assessed at 2 weeks, 4 to 6 weeks, 10 to 12 weeks, 6 months, and 1- and 2-year intervals. The minimum follow-up period was 6 months; the average follow-up period was 18 months. The principal outcome analyzed was the Disabilities of the Arm, Shoulder, and Hand score. Secondary outcomes included grip strength, range of motion, surgical procedure time, complications, and radiographic parameters. The groups were equal with respect to age, gender, fracture subtype, and number of workers' compensation cases.

RESULTS

No significant difference was found in the Disabilities of the Arm, Shoulder, and Hand scores, our primary outcome. The dorsal plate group, however, showed a higher complication rate when compared with the external fixator group. The plate group had significantly longer tourniquet times when compared with the external fixator group. The plate group also had higher levels of pain at 1 year when compared with the external fixator group; however, this equalized after hardware removal. The external fixator group showed an average grip strength of 97% compared with the normal side and 86% in the dorsal plate group.

CONCLUSIONS

At midterm analysis the dorsal plate group showed a significantly higher complication rate compared with the external fixator group; therefore enrollment in the study was terminated. The dorsal plate group also showed statistically significant higher levels of pain, weaker grip strength, and longer surgical and tourniquet times. Based on these results we cannot recommend the use of dorsal plates in treating complex intra-articular fractures of the distal radius.

Coordinated secretion of alkaline phosphatase into serum and intestine in fat-fed rats

BACKGROUND

Fat feeding increases the activity of intestinal alkaline phosphatase in the serum. The mechanism underlying this increase is unknown. Surfactant-like particles (SLP) secreted by enterocytes have been implicated in this phenomenon.

OBJECTIVE

To study the effect of feeding fish oil and protein synthesis inhibitors on alkaline phosphatase activity in serum and in different intestinal fractions.

METHODS

Male albino rats were fed 2 mL of fish oil and were injected cycloheximide or actinomycin D. Alkaline phosphatase activity was determined in the serum and intestinal fractions (SLP, mucosa, muscularis).

RESULT

Feeding fish oil significantly elevated alkaline phosphatase activity in serum (p< 0.001) and intestinal mucosa (p< 0.01). Administration of cycloheximide or actinomycin D significantly reduced alkaline phosphatase activity in serum (p< 0.01) and in intestinal mucosa (p< 0.05). BCIP staining of brush border alkaline phosphatase activity in acrylamide gels yielded similar results.

CONCLUSIONS

These findings suggest a co-ordination between alkaline phosphatase synthesis and its assembly into lipoprotein vesicles, such as SLP, secreted by enterocytes in response to fat feeding.

Rituximab for autoimmune haemophilia: a proposed treatment algorithm

We previously reported durable complete responses following brief courses of rituximab and prednisone with or without cyclophosphamide in four patients with autoimmune haemophilia and inhibitor titres of 5-60 BU. We report here responses to this monoclonal anti-CD20 antibody in four additional patients, including two patients with inhibitor titres >200 BU. Factor VIII levels became normal 2-35weeks after 4 or 8 weekly doses of rituximab, brief courses of prednisone and in one patient immunoglobulin. Complete responses are ongoing at 10 months in two patients. Two patients relapsed: a patient whose initial inhibitor titre was 525 BU relapsed at 3.5 months and a long-term prednisone-dependent patient at 8.5 months. Both responded to second courses of rituximab and prednisone and are in remission. Our experience suggests that rituximab is a safe and effective addition to immunosuppression with prednisone and cyclophosphamide to treat autoimmune haemophilia, and may permit early discontinuation or even avoidance of these potentially toxic agents. High-titre inhibitor patients, however, may require multiple courses of rituximab or the addition of cyclophosphamide. Pending randomized studies, we propose an algorithm based on our experience and other reports for incorporating rituximab in the treatment of this rare disorder.

Synthetic mannosides act as acceptors for mycobacterial α1-6 mannosyltransferase

A series of synthetic mannosides was screened in a cell-free system for their ability to act as acceptor substrates for mycobacterial mannosyltransferases. Evaluation of these compounds demonstrated the incorporation of [14C]Man from GDP-[14C]Man into a radiolabeled organic-soluble fraction and analysis by thin layer chromatography and autoradiography revealed the formation of two radiolabeled products. Each synthetic acceptor was capable of accepting one or two mannose residues, resulting in a major and a minor mannosylated product. Both products from each acceptor were isolated and their mass was confirmed by fast-atom bombardment-mass spectrometry (FABMS). Characterization of each mannosylated product by exo-glycosidase digestion. acetolysis and linkage analysis by gas chromatography mass spectrometry of partially per-O-methylated alditols, revealed only alpha1-6-linked products. In addition. the antibiotic amphomycin selectively inhibited the formation of mannosylated products suggesting polyprenolmonophosphate-mannose (C15 50-P-Man) was the immediate mannose donor in all mannosylation reactions observed. The ability of synthetic disaccharides to act as acceptor substrates in this system, is most likely due to the action of a mycobacterial polyprenol-P-Man:mannan alpha1-6 mannosyltransferase involved in the biosynthesis of linear alpha1-6-linked lipomannan.

Ulnar nerve elongation and excursion in the cubital tunnel after decompression and anterior transposition

We studied the elongation and excursion of cadaveric ulnar nerves during elbow flexion in control conditions and after in situ decompression and anterior subcutaneous transposition. We found that the normal nerve had the greatest elongation (23%) and excursion (14 mm) in the epicondylar groove. Decompression did not alter the excursion, but significantly reduced the elongation in the groove (6%) and increased it proximally (19%). After anterior subcutaneous transposition, the nerve segment which was originally in the groove elongated with elbow extension to the same extent as occurred with the normal nerve during flexion.

Feasibility of partial A2 and A4 pulley excision: residual pulley strength

We investigated residual digital flexor pulley strengths after 75% excision of the A2 and A4 pulleys. For direct pull-off tests, A2 and A4 pulleys from cadaveric fingers were tested by pulling on a loop of flexor digitorum profundus tendon through the pulley. For functional loading tests, fingers were positioned with the metacarpophalangeal joint flexed to 90 degrees for A2 testing, and with the proximal interphalangeal joint in 90 degrees flexion for A4 testing (with all other joints in full extension). Excision of 75% of A2 and A4 pulleys reduced pulley strengths determined by both testing methods. For the functional loading tests, which are more clinically relevant, mean tendon forces at failure after partial excision of A2 and A4 pulleys were 224 and 131 N respectively, which is sufficient to withstand flexor tendon forces expected during activities of daily living.

Passive and active rehabilitation for partial lacerations of the canine flexor digitorum profundus tendon in zone II

The purpose of this study was to compare the effect of unrestricted active versus passive mobilization on the gliding function and structural properties (ultimate load and stiffness) of repaired and nonrepaired canine flexor digitorum profundus tendons following partial laceration at 1 week. Using a radiographic method, normalized tendon gliding of the flexor digitorum profundus tendon adjacent to the metacarpal bone and total joint rotation were shown to be significantly greater in passive than in active tendons. Each group differed from their control group, however, by an average of only 5%. Both rehabilitation (active vs. passive) and treatment (repair vs. nonrepaired) of the partial tendon laceration significantly affected gap formation. Both active rehabilitation and repair of the laceration significantly increased gap formation compared with passive rehabilitation and nonrepair of the partial laceration. Rehabilitation did not significantly affect the normalized ultimate loads and stiffness in the passive and active groups but the nonrepair groups displayed significantly higher ultimate loads and stiffness than the repair groups.

Feasibility of partial A2 and A4 pulley excision: effect on finger flexor tendon biomechanics

We investigated the effect of partial excision of the A2 and A4 digital pulleys, separately and in combination, on finger angular rotation and the energy for finger flexion. Statistically significant decreases in angular rotation resulted only after 50% and 75% excision of A2, A4, or A2 and A4 in combination. Work of flexion trends were weak and none of the changes were statistically significant. Although optimal finger function relies on the integrity of the A2 and A4 pulleys to maintain the efficiency of the digital flexor system, these data suggest that the A2 and A4 pulleys can be excised up to 25%, either separately or in combination, without significant effects on angular rotation. Decreases in total angular range of motion after 50% and 75% pulley excision were small, even for combined pulley excision (9 degrees +/- 3 degrees and 15 degrees +/- 5 degrees [mean +/- SD], respectively), and may be clinically acceptable.

Mapping of a new autosomal dominant spinocerebellar ataxia to chromosome 22

The autosomal dominant cerebellar ataxias (ADCAs) are a clinically and genetically heterogeneous group of disorders. The clinical symptoms include cerebellar dysfunction and associated signs from dysfunction in other parts of the nervous system. So far, five spinocerebellar ataxia (SCA) genes have been identified: SCA1, SCA2, SCA3, SCA6, and SCA7. Loci for SCA4 and SCA5 have been mapped. However, approximately one-third of SCAs have remained unassigned. We have identified a Mexican American pedigree that segregates a new form of ataxia clinically characterized by gait and limb ataxia, dysarthria, and nystagmus. Two individuals have seizures. After excluding all known genetic loci for linkage, we performed a genomewide search and identified linkage to a 15-cM region on chromosome 22q13. A maximum LOD score of 4.3 (recombination fraction 0) was obtained for D22S928 and D22S1161. This distinct form of ataxia has been designated "SCA10." Anticipation was observed in the available parent-child pairs, suggesting that trinucleotide-repeat expansion may be the mutagenic mechanism.

Targeted disruption of SHIP leads to hemopoietic perturbations, lung pathology, and a shortened life span

SHIP is a 145-kD SH2-containing inositol-5-phosphatase widely expressed in hemopoietic cells. It was first identified as a tyrosine phosphoprotein associated with Shc in response to numerous cytokines. SHIP has been implicated in FcgammaRIIB receptor-mediated negative signaling in B cells and mast cells and is postulated to down-regulate cytokine signal transduction in myeloid cells. To define further its role in the proliferation and differentiation of hemopoietic progenitors, as well as its function in mature cells, we have generated embryonic stem cells and mice bearing a targeted disruption of both SHIP alleles. Here we show that although SHIP null mice are viable and fertile, they fail to thrive and survival is only 40% by 14 weeks of age. Mortality is associated with extensive consolidation of the lungs resulting from infiltration by myeloid cells. Increased numbers of granulocyte-macrophage progenitors are observed in both the bone marrow and spleen of SHIP-/- mice, perhaps as a consequence of hyper-responsiveness to stimulation by macrophage-colony stimulating factor, granulocyte-macrophage colony stimulating factor, interleukin-3, or Steel factor as observed in vitro. In contrast, numbers of bone marrow lymphoid and late erythroid progenitors (CFU-E) are reduced. Thus, homozygous disruption of SHIP establishes the crucial role of this molecule in modulating cytokine signaling within the hemopoietic system and provides a powerful model for further delineating its function.

The effect of partial excision of the A2 and A4 pulleys on the biomechanics of finger flexion

The purpose of this study was to investigate the effect of partial excision of the A2 and A4 pulleys on digital angular rotation and the energy required to flex the finger. Partial excision of A2 resulted in a statistically significant decrease in angular rotation of 3 and 5% after 50 and 75% excision, respectively. Partial excision of A4 failed to produce any significant differences in angular rotation. Combined partial excision of A2 and A4 resulted in a significant decrease of 5 and 8% after 50 and 75% excision, respectively. Significant differences in work of flexion occurred only after excision of 75% of the A2 pulley. Although optimal finger function relies on the integrity of the A2 and A4 pulleys which maintain the efficiency of the digital flexor system, these data suggest that 25% of the A2 pulley, up to 75% of the A4 and 25% of the A2 and A4 together can be excised without significant effects on angular rotation.

The effects of multiple-strand suture methods on the strength and excursion of repaired intrasynovial flexor tendons: a biomechanical study in dogs

This study was designed to determine the effects of in vivo multistrand, multigrasp suture techniques on the strength and gliding of repaired intrasynovial tendons when controlled passive motion rehabilitation was used. Twenty-four adult mongrel dogs were divided into 4 groups and their medial and lateral forepaw flexor tendons were transsected and sutured by either the Savage, the Tajima, the Kessler, or the recently developed 8-strand suture method. The tendon excursion, joint rotation, and tensile properties of the repaired tendons were evaluated biomechanically at 3 and 6 weeks after surgery. It was found that neither time nor suture method significantly effected proximal and distal interphalangeal joint rotation or tendon excursion when the 4 techniques were compared to each other. Normalized load value (experimental/control) was significantly affected by both the suture method and the amount of time after surgery, however. The Savage and 8-strand repair methods had significantly greater strength than did the Tajima method at each time interval (p < .05 for each comparison). In addition, the 8-strand method had significantly greater normalized load values than did the Savage method at each time interval (p < .05 for each comparison). Normalized stiffness (experimental/control) for the 8-strand repair method was significantly greater than that for the Tajima and Savage methods at 3 and 6 weeks after surgery (p < .05). In addition, the normalized stiffness values for the 6-week groups was significantly greater than those for the 3-week groups (p < .05). It was concluded that the method of tendon suture was a significant variable insofar as the regaining of tendon strength was concerned and that the newer low-profile 8-strand repair method significantly expands the safety zone for the application of increased in vivo load during the early stages of rehabilitation.

Human acetyltransferase polymorphisms

Conjugation of primary amino and hydroxylamino groups with acetate, catalyzed by acetyl CoA-dependent arylamine acetyltransferase (NAT) enzymes, may play an important role in the intricate series of metabolic pathways that produce or prevent toxicity following exposure to homo- and heterocyclic arylamine and hydrazine xenobiotics. Two independently regulated and kinetically distinct human acetyltransferases are now known to exist, namely NAT1 and NAT2. Interindividual variation in NAT2 function is associated with the classical isoniazid acetylation polymorphism which was discovered over forty years ago. At last count, fifteen variant alleles at the NAT2 gene locus have been linked to the isoniazid 'acetylator phenotype', and each of these can be identified in population studies using specific PCR-based genotyping tests. On the other hand, NAT1 shows kinetic selectivity for compounds whose disposition is unrelated to the classical isoniazid acetylation polymorphism. NAT1 expression is also phenotypically variable in human populations, at least in part due to allelic differences at the NAT1 gene locus. Nine NAT1 variant alleles have been described to date, of which NAT1* 14 and NAT1* 15 clearly produce defective NAT1 proteins and lead to functional impairment in the metabolism of NAT1-selective substrates both in vivo and in vitro. On the other hand, it has been reported that the NAT1* 10 variant associates with elevated NAT1 activity and increased risk for cancers of the bladder and colon. Because of the important toxicologic consequences of allelic variation in NAT1 and NAT2 function for the metabolic activation of arylamine and heterocyclic amine procarcinogens, further studies are needed to improve our understanding of the extent of NAT allelic variation, to determine the functional capacity of each variant gene product, and to develop accurate methods of detecting them in population and epidemiological studies.

Isolation of chromosome 18-specific brain transcripts as positional candidates for bipolar disorder

Several studies have proposed the existence of susceptibility loci for bipolar disorder on chromosome 18. To identify possible candidate genes for this disease, we isolated brain-expressed transcripts by direct cDNA selection on chromosome 18-specific biotinylated cosmid clones. Longer cognate cDNA clones of the selected cDNAs were isolated from a normalized infant brain cDNA library. Physical mapping by PCR on a panel of somatic cell hybrids was conducted by the use of primers derived from partial sequences on either the 5' or 3' ends of the clones. In our initial analysis, 48 cDNA clones were found to be chromosome 18-specific, mapping to different subchromosomal regions. Sequence redundancy among these clones yielded 30 unique transcripts, five of which were represented in previously known genes. Further sequencing of the remaining 25 unique cDNA clones confirmed the absence of significant homology to known genes, indicating that these transcripts represented novel genes. Mapping with the use of a radiation hybrid panel positioned the brain cDNAs to within = 100 to 1100 kb from reference sequence tag sites (STSs) and assembled them into six high resolution linkage groups. The majority of the transcripts were found to cluster to discrete locations on 18p and 18q, previously hypothesized as susceptibility regions for bipolar disorder, identifying them as positional candidate genes.