Use of Crotalidae equine immune F(ab')2 antivenom for treatment of an Agkistrodon envenomation

INTRODUCTION

Anavip (F(ab')₂AV) is a lyophilized F(ab')₂ immunoglobulin fragment derived from horses immunized with venom from Bothrops asper and Crotalus durissus. It was approved by the FDA in 2015 for treatment of North American rattlesnake envenomation but not for Agkistrodon envenomation. Published data regarding the efficacy and safety of Anavip in treating Agkistrodon envenomations is limited. We present a case of a patient treated with Anavip after confirmed Agkistrodon laticinctus envenomation.

CASE DETAILS

A 77 year-old man was bitten on his fifth finger by a captive A. laticinctus. He was taken to a local emergency department where he received a 10 vial initial dose of F(ab')₂AV for pain and swelling and was transferred. At the receiving facility, his pain had improved and his swelling had not progressed. Over the next 30 h, his platelets declined to 132,000/mm³ and he received an additional 4 vials of F(ab')₂AV. The remainder of his course was unremarkable with complete recovery by 3 months.

DISCUSSION

This case provides an additional published datapoint on the use of this F(ab')₂AV in the treatment of envenomation by Agkistrodon.

A Unified Treatment of the Relationship Between Ligand Substituents and Spin State in a Family of Iron(II) Complexes

The influence of ligands on the spin state of a metal ion is of central importance for bioinorganic chemistry, and the production of base-metal catalysts for synthesis applications. Complexes derived from [Fe(bpp)2 ](2+) (bpp=2,6-di{pyrazol-1-yl}pyridine) can be high-spin, low-spin, or spin-crossover (SCO) active depending on the ligand substituents. Plots of the SCO midpoint temperature (T1/2 ) in solution vs. the relevant Hammett parameter show that the low-spin state of the complex is stabilized by electron-withdrawing pyridyl ("X") substituents, but also by electron-donating pyrazolyl ("Y") substituents. Moreover, when a subset of complexes with halogeno X or Y substituents is considered, the two sets of compounds instead show identical trends of a small reduction in T1/2 for increasing substituent electronegativity. DFT calculations reproduce these disparate trends, which arise from competing influences of pyridyl and pyrazolyl ligand substituents on Fe-L σ and π bonding.

Efficacy of follow-up and contact tracing of women who test positive for genital tract chlamydia trachomatis prior to pregnancy termination

We examined the efficacy of follow-up, contact tracing and the need for retreatment in women who were screen-positive for genital tract Chlamydia trachomatis prior to termination of pregnancy. Eighty-six of 1363 (6.3%) women screened positive. These women were significantly younger than those who screened negative (P < 0.0001). The genitourinary medicine (GUM) clinic was notified of 73 (84.9%) screen-positive women and 41 (47.7%) attended for follow-up. Contact tracing was undertaken in 38 (92.7%) women who attended and 29 (70.7%) women who attended required retreatment for Chlamydia. The median duration between pregnancy termination and GUM clinic attendance was significantly longer in women who required retreatment compared to those who did not require retreatment (P = 0.003). In conclusion, follow-up and contact-tracing of women who screen positive for genital tract C. trachomatis was incomplete. This may substantially compromise the cost-effectiveness of a screen-and-treat programme.

Mlh1 deficiency accelerates myeloid leukemogenesis in neurofibromatosis 1 (Nf1) heterozygous mice

Defects in DNA mismatch repair (MMR) have been implicated in the genesis of a diverse set of human cancers. Recent studies have suggested that one of the targets of MMR is the neurofibromatosis 1 (NF1) gene. To evaluate the contribution of Mlh1 MMR deficiency to Nf1 tumorigenesis, Mlh1-/-;Nf1+/- mice were generated. All Mlh1-/-;Nf1+/- mice (n=21) were dead by 260 days compared to none of the Nf1+/- mice. In all, 50% of the Mlh1-/-;Nf1+/- mice were dead at 150 days compared to 252 days for Mlh1-/- mice. Nine of the Mlh1-/-;Nf1+/- mice were found to harbor intrathoracic NOS2-immunoreactive myeloid leukemias similar to the hematopoietic malignancies observed in older Nf1+/- mice. As expected, significant microsatellite instability was observed in six of six tumors and neurofibromin expression was lost in all tumors analysed. These results suggest that MMR deficiency can accelerate myeloid leukemogenesis in Nf1+/- mice, presumably by inactivating Nf1 gene expression.

Bacterial pathogens of otitis media and sinusitis: detection in the nasopharynx with selective agar media

Carriage rates for the bacterial pathogens associated with otitis media (Streptococcus pneumoniae [SP], Hemophilus influenzae [HI], and Moraxella catarrhalis [MC]) are of interest. Culture on three selective agars was compared with culture on two standard agars to determine the more accurate method for detection of these species in the nasopharynx of healthy children. Weekly samples were obtained in winter from 18 healthy children (ages 1 through 9 years) as part of a longitudinal study. A 0.1-mL sample of 116 nasopharyngeal aspirate/washes was inoculated onto each of five agars. Two were standard (sheep blood and chocolate), and three were selective (blood with gentamicin for SP; chocolate with vancomycin, bacitracin, and clindamycin for HI; blood with amphotericin B, vancomycin, trimethoprim, and acetazolamide for MC). One technician read the standard plates and another the selective; both were blinded to the results of the other. SP was found in 44% of samples with selective agar versus 25% with standard agar; HI was found in 31% with selective versus 9% with standard; MC was found in 56% with selective versus 37% with standard. Overall, 80% of samples had one or more pathogens detected with selective agars as compared with 58% with standard agars (P =.0004). Selective agars were more accurate than standard agars for detecting otitis pathogens in the nasopharynx, where they are a common part of normal flora in healthy children.

Abortion training in U.S. obstetrics and gynecology residency programs, 1998

CONTEXT

Since the late 1970s, the number of obstetrics and gynecology residency programs providing abortion training in the United States has steadily decreased. Given the documented shortage of abortion providers, assessing and ensuring the availability of abortion training in graduate medical education is critical.

METHODS

In 1998, the National Abortion Federation surveyed the 261 accredited U.S. residency programs in obstetrics and gynecology, and analyzed the availability of first- and second-trimester abortion training.

RESULTS

Of the 179 programs that responded to the survey, 81% reported that they offer first-trimester abortion training--46% routinely and 34% as an elective. Seventy-four percent of programs offer second-trimester training--44% routinely and 29% as an elective. Some programs that do not offer training give residents the option of obtaining it elsewhere. While 26% of programs indicated that all residents in their programs receive abortion training, 40% said that fewer than half are trained, including 14% that train no residents. The operating room is the most common training site: Fifty-nine percent of programs reported that abortion training takes place in the operating room.

CONCLUSIONS

After a decades-long decline in the availability of abortion training, opportunities for abortion training have increased. However, there is reason to be cautious in interpreting these results, including possible response bias and pressure to report the availability of abortion training because of new guidelines from the Accreditation Council for Graduate Medical Education.

Mlh1 deficiency enhances several phenotypes of Apc(Min)/+ mice

Defects in APC and DNA mismatch repair genes are associated with a strong predisposition to colon cancer in humans, and numerous mouse strains with mutations in these genes have been generated. In this report we describe the phenotype of Min/+ Mlh1-/- mice. We find that these doubly mutant mice develop more than three times the number of intestinal adenomas compared to Min/+ Mlh1+/+ or +/- mice but that these tumors do not show advanced progression in terms of tumor size or histological appearance. Full length Apc protein was not detected in the tumor cells from Min/+ Mlh1-/- mice. Molecular analyses indicated that in many tumors from Min/+ Mlh1-/- mice, Apc was inactivated by intragenic mutation. Mlh1 deficiency in Min/+ mice also led to an increase in cystic intestinal crypt multiplicity as well as enhancing desmoid tumorigenesis and epidermoid cyst development. Thus, Mlh1 deficiency influences the somatic events involved in the development of most of the phenotypes associated with the Min mutation. Oncogene (2000).

Predominant interactions between mu-conotoxin Arg-13 and the skeletal muscle Na+ channel localized by mutant cycle analysis

High-affinity mu-conotoxin block of skeletal muscle Na+ channels depends on an arginine at position 13 (Arg-13). To understand both the mechanism of toxin interaction and the general structure of its binding site in the channel mouth, we examined by thermodynamic mutant cycle analysis the interaction between the critical Arg-13 and amino acid residues known to be in the channel's outer vestibule. Arg-13 interacts specifically with domain II Glu-758 with energy of about -3.0 kcal/mol, including both electrostatic and nonelectrostatic components, and with Glu-403 with energy of about -2.0 kcal/mol. Interactions with the other charged residues in the outer vestibule were shown to be almost entirely electrostatic, because these interactions were maintained when Arg-13 was replaced by lysine. These results place the bound Arg-13 at the channel mouth adjacent to the P (pore) loops of domains I and II. Distance estimates based on interaction energies suggest that the charged vestibule residues are in relative positions similar to those of the Lipkind-Fozzard vestibule model [Lipkind, G. M., and Fozzard, H. A. (1994) Biophys. J. 66, 1-13]. Kinetic analysis suggests that Arg-13 interactions are partially formed in the ligand-channel transition state.

Hospital-acquired urinary tract infections in the pediatric patient: a prospective study

To determine through a prospective study the characteristics of hospital-acquired urinary tract infections (HAUTI) in children, 525 children subjected to bladder catheterization during a hospital admission were identified through surveillance of 12,316 admissions during a 24-month period. Urine culture results were available for 296 (56.4%) of the catheterized patients. In addition 12 noncatheterized children with a documented HAUTI were identified. The clinical courses of all patients with a HAUTI were followed for at least 6 months after their last HAUTI during the study period. Forty-four patients, 1 week to 17 years of age, with 1 or more HAUTI during a hospital unit admission were identified. A total of 51 HAUTI occurred. Thirty-nine (76.5%) of the infections occurred in patients subjected to catheterization. Thirty-two (10.8%) of 296 catheterized patients developed a HAUTI. Forty-three (84.3%) of the 51 infections were single organism infections. One HAUTI was associated with a wound infection with the same organism and one with a concurrent bacteremia with the same organism. Relapses were seen after 4 HAUTI. One reinfection was identified. There were no deaths directly associated with a HAUTI. Hospitalized children subjected to urinary tract catheterization are at significant risk for HAUTI. Complications are infrequent and not life-threatening.

Carbon-isotope discrimination by leaves of Flaveria species exhibiting different amounts of C3-and C 4-cycle co-function

Carbon-isotope ratios were examined as δ(13)C values in several C3, C4, and C3-C4 Flaveria species, and compared to predicted δ(13)C, values generated from theoretical models. The measured δ(13)C values were within 4‰ of those predicted from the models. The models were used to identify factors that contribute to C3-like δ(13)C values in C3-C4 species that exhibit considerable C4-cycle activity. Two of the factors contributing to C3-like δ(13)C values are high CO2 leakiness from the C4 pathway and pi/pa values that were higher than C4 congeners. A marked break occurred in the relationship between the percentage of atmospheric CO2 assimilated through the C4 cycle and the δ(13)C value. Below 50% C4-cycle assimialtion there was no significant relationship between the variables, but above 50% the δ(13)C values became less negative. These results demonstrate that the level of C4-cycle expression can increase from, 0 to 50% with little integration of carbon transfer from the C4 to the C3 cycle. As expression increaces above 50%, however, increased integration of C3- and C4-cycle co-function occurs.

Use of an anaerobic culture jar in processing pediatric throat cultures

Two hundred consecutive throat cultures from a Pediatric Walk-in Clinic were processed, using both aerobic and anaerobic culture techniques. The 35 aerobic isolates of group A beta-hemolytic streptococci (BHS) were all confirmed anaerobically as well, and there were two additional isolates detected only by the anaerobic technique. Of these 37 bacitracin-sensitive isolates, only 24 (65%) could be identified at 24 hours using the aerobic technique, compared to 29 (78%) using the anaerobic technique. In contrast to this relatively small effect upon the isolation of group A BHS, the yield of BHS from groups B, C, F, and G was more than doubled by the anaerobic technique. The confusion engendered by the improved detection of these bacitracin-resistant BHS using the anaerobic technique offset the small advantage in thoroughness and speed of detection of group A organisms. On this account, until more is known about the possible significance of isolating nongroup A BHS in the pharynx, the advisability of using an anaerobic culture jar to process pediatric throat cultures remains uncertain.

Effect of dredge spoil deposition on fecal coliform counts in sediments at a disposal site

The most-probable-number of fecal coliforms in sediments was monitored at the New London dump site in Long Island Sound during the deposition of dredge spoil from the Thames River. Although the geometric mean for fecal coliforms at five stations in the river was 14,000/100 ml before dredging commenced, the deposition of this material did not increase the incidence of fecal coliforms at 17 spoil stations and 13 control stations in the disposal and surrounding areas. Fecal coliforms appear to occur only in the surface sediment material and are diluted by the subsurface material during the dredging operation. Fecal coliform analyses of bottom waters during high and low tides indicated that the flow of water from the Thames River played a major role in determining the most-probable-number of fecal coliforms in the sediments at the disposal site.