scholarly journals Evidence of Regeneration of Testicular and Epididymal Tissue Structure and Function Following Withdrawal from Sub-chronic Khat Exposure: Studies in the Rabbit Animal Model

Author(s):  
Albert W. Nyongesaa ◽  
Esther M. Malukib ◽  
Jemimah A. Simbaunib

Khat, Catha edulis, use is rampant in Eastern Africa and Middle East countries with associated reports of reproductive function impairment in the body of the user. Reports on recovery post long-term khat exposure are obscure. The present study investigated evidence of restoration of testicular and epididymal structure and function during withdrawal from cytotoxic damage caused by sub-chronic exposure of khat extract. Twenty-eight male rabbits were divided into 7 groups of 4 rabbits each. Group I (control) was administered normal saline while groups II, III and IV were administered 1.0 g/kg, 10 g/kg and 20 g/kg body weight of khat extract, respectively, via oral gavage on alternate days of the week for 12 weeks. Blood samples from animals were collected for hormonal assays followed by euthanasia using 26.4 mg/kg body weight of Sagatal sodium intramuscularly for testicular and epididymal histology. Group V, VI and VII were administered 1.0 g/kg, 10 g/kg and 20 g/kg body weight of khat extract, respectively, orally on alternate days of the week for 12 weeks followed by 1-month withdrawal period, blood samples collected for hormone assays and animals sacrificed for testicular and epididymal histology. High khat dose, 20 g/kg body weight, at sub-chronic exposure caused degeneration in spermatogenic cells with accompanying decrease in plasma FSH and testosterone. Histological output of Sertoli cells, Leydig cells and epididymal epithelium appeared unaffected in treatment groups. Post withdrawal data showed apparent regeneration of seminiferous epithelium and restoration of plasma FSH and testosterone comparable to control. It appears khat extract preferentially affected germ cell spermatogonia and subsequent daughter cells while stem cell spermatogonia were unaffected and contributed to regeneration of germinal epithelium and endocrine function.

Author(s):  
Laksmi Wulandari ◽  
Gatot Soegiarto ◽  
Anna Febriani ◽  
Farah Fatmawati ◽  
Wirya Sastra Amran

Abstract Introduction There are a substantial number of lung cancer patients with negative mutations in Indonesia. This type of cancer is deemed to be the major contributor of lung cancer patient’s death. However, reseaerch related to therapy using vinorelbine combined with platinum-based compounds is still scarce in Indonesia. The aim of this study was to compare the efficacy and tolerability between vinorelbine and carboplatin with vinorelbin and cisplatin in stage III-IV epidermal growth factor receptor (EGFR) mutations-negative non-small cell lung cancer (NSCLC). Methods The participants were divided into two groups—group I(vinorelbine–carboplatin) and group II (vinorelbine–cisplatin). The participants were assessed based on several measurement criteria. Not only Eq-5D was performed, but the body weight and response evaluation criteria for solid tumors (RECIST) were also examined. The participants received chemotherapy for four cycles (1 cycle = 21 days). Results The quality of life was considered stable in 60% of group I and 60% of group II (p=0.255). In both groups, 46.67% of participants had an increased body weight, while the other 20.00% was stable (p = 1.000). In terms of RECIST evaluation after the second cycle, 80.00% of group I and 86.67% of group II were considered to have a stable disease, with 20% of group I and none of group II had partial response (p = 0.027). However, after the fourth cycle, there were no significant difference between the groups (p = 0.734). Conclusion In EGFR mutation-negative NSCLC patients, the combination of vinorelbine and carboplatin showed comparable outcomes to vinorelbine and cisplatin chemotherapy with no significant differences.


1998 ◽  
Vol 26 (2) ◽  
pp. 178-183 ◽  
Author(s):  
R. D. Branson ◽  
R. S. Campbell ◽  
K. Davis ◽  
D. T. Porembka

We compared the effects of humidity delivered by the circle system at low fresh gas flows (FGF) with a conventional two-limb and coaxial circuit on the structure and function of the tracheobronchial epithelium in dogs. Animals were anaesthetized and mechanically ventilated using an anaesthesia ventilator to maintain normocarbia. Group I (control) animals received a FGF equal to the required minute ventilation mimicking an open circuit technique. Group II and III animals had FGF set at 20% of the required minute ventilation. Group II used a two-limb circuit and Group III used a coaxial circuit. Relative humidity and temperature of inspired gases were measured at baseline and hourly afterwards. In the first experiment, biopsies of the tracheobronchial tree were obtained bronchoscopically at baseline and then hourly for six hours. Microscopic examination of these samples allowed calculation of mean ciliary length. In the second experiment, tracheal mucus flow velocity (TMFV) was measured at baseline and hourly afterward, using a cinebroncho-fibrescopic method. Delivered absolute humidity was greatest with low FGF and the coaxial circuit, followed by low FGF and a conventional circuit, and high FGF (15±1.4 vs 9±0.8 vs 5±0.4 mg H2O, P<0.01) after two hours. Mean cilia length (μ m) and TMFV (mm/min) fell during the first hour in all three groups. At hour two TMFV returned to baseline in Group III and was significantly greater than Groups I and II (0.8±0.4 vs 8.6±1.1 vs 15.4±2.1, P<0.001). Mean ciliary length demonstrated a similar pattern with reductions from baseline in all three groups for the first two hours. Groups II and III had an increase in cilia length beginning at hour three and were both significantly greater than Group I at hours 3 through 6 (1.3±0.5 vs 3.2±1.1 vs 4.2±0.8, P <0.001). Alterations in tracheobronchial structure and function result from exposure to dry gases and are amplified by the duration of exposure. Our findings suggest a minimum of 12 to 15 mg H2O/l is necessary to prevent these alterations. In this study, the combination of low FGF and a coaxial anaesthesia circuit reached this minimum threshold more quickly than a conventional two-limb circuit.


‘Cellular structure and function’ covers the roles, structures, and functions of the main four types of macromolecules of the human body, namely proteins, lipids, carbohydrates, and nucleic acids. For these macromolecules, the roles and types of each class are discussed (for proteins this includes their roles as structural proteins and enzymes and their kinetics; for lipids, the roles and types of lipid found in the body are considered; for carbohydrates, their roles including structural and metabolic are discussed; and the structure of nucleic acids is described). Then follows a description of the organization of the cell, including the plasma membrane and its components, and the intracellular organelles. Cell growth, division, and apoptosis are covered, as are the formation of gametes, and finally the principles of how cellular functions can be modulated by pharmacological agents through receptors and signalling pathways are discussed.


2002 ◽  
Vol 74 (1) ◽  
pp. 89-94
Author(s):  
Tian Yongqiang ◽  
Zhao Xingxu ◽  
Wang Minqiang ◽  
Lu Zhonglin ◽  
Zhang Rongchang

AbstractThe concentrations of growth hormone (GH), insulin (Ins), tri-iodothyronine (T3) and thyroxine (T4) in blood samples of growing yaks during different bimonthly seasons were determined by radioimmunoassay. The changes of body weight of growing yaks and composition of grass grazed were measured accordingly. The seasonal changes of hormones were significant (P < 0·01 or P < 0·05). Within season, the variances of hormones depended upon the different growing stages. The body-weight gains in the different groups varied in different seasons, increase being significant in May, July and September, decrease being significant from January to May. Correlation analysis indicated that T4 concentration had a significant positive correlation with the body weight of the growing yaks(r = 0·2509, P < 0·05) and other hormones did not have any significant correlation with body weight. The results showed that the annual cycle of weight loss and gain was attributed to the seasonal change of nutrition status. The seasonal change of the assayed hormones depended on the grass growth.


1969 ◽  
Vol 69 (5) ◽  
pp. 1075
Author(s):  
Faustena Blaisdell ◽  
Catherine Parker Anthony

2020 ◽  
Vol 21 (8) ◽  
pp. 2764
Author(s):  
Taremekedzwa Allan Sanyanga ◽  
Özlem Tastan Bishop

Human carbonic anhydrase 8 (CA-VIII) is an acatalytic isoform of the α -CA family. Though the protein cannot hydrate CO2, CA-VIII is essential for calcium (Ca2+) homeostasis within the body, and achieves this by allosterically inhibiting the binding of inositol 1,4,5-triphosphate (IP3) to the IP3 receptor type 1 (ITPR1) protein. However, the mechanism of interaction of CA-VIII to ITPR1 is not well understood. In addition, functional defects to CA-VIII due to non-synonymous single nucleotide polymorphisms (nsSNVs) result in Ca2+ dysregulation and the development of the phenotypes such as cerebellar ataxia, mental retardation and disequilibrium syndrome 3 (CAMRQ3). The pathogenesis of CAMRQ3 is also not well understood. The structure and function of CA-VIII was characterised, and pathogenesis of CAMRQ3 investigated. Structural and functional characterisation of CA-VIII was conducted through SiteMap and CPORT to identify potential binding site residues. The effects of four pathogenic nsSNVs, S100A, S100P, G162R and R237Q, and two benign S100L and E109D variants on CA-VIII structure and function was then investigated using molecular dynamics (MD) simulations, dynamic cross correlation (DCC) and dynamic residue network (DRN) analysis. SiteMap and CPORT analyses identified 38 unique CA-VIII residues that could potentially bind to ITPR1. MD analysis revealed less conformational sampling within the variant proteins and highlighted potential increases to variant protein rigidity. Dynamic cross correlation (DCC) showed that wild-type (WT) protein residue motion is predominately anti-correlated, with variant proteins showing no correlation to greater residue correlation. DRN revealed variant-associated increases to the accessibility of the N-terminal binding site residues, which could have implications for associations with ITPR1, and further highlighted differences to the mechanism of benign and pathogenic variants. SNV presence is associated with a reduction to the usage of Trp37 in all variants, which has implications for CA-VIII stability. The differences to variant mechanisms can be further investigated to understand pathogenesis of CAMRQ3, enhancing precision medicine-related studies into CA-VIII.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Samuel Tung-Hsing Chiang ◽  
Shang-Min Yeh ◽  
Yi-Chen Chen ◽  
Shiun-Long Lin ◽  
Jung-Kai Tseng

The purpose of this study was to investigate the protective role of orally administered taurine against diabetic retinal changes via electroretinogram (ERG) and retinal histology on rabbits. Rabbits were randomly assigned into groups: Group I (vehicle administration only); Group II (diabetes: induced by 100 mg/kg alloxan injection); Group III (diabetes and fed with 200 mg/kg taurine); and Group IV (diabetes and fed with 400 mg/kg taurine). The body weight and blood glucose levels of the rabbits were monitored weekly. The ERG was measured on weeks 5 and 15. Retinal histology was analyzed in the end of the experiment. Results revealed that a taurine supplement significantly ameliorates the alloxan-induced hyperglycemia and protects the retina from electrophysiological changes. Group II showed a significant(P<0.05)change in the mean scotopic b-wave amplitude when compared to that of Group I, whereas the diabetic rabbits treated with taurine (Group III and IV) were analogous to Group I. Histologically, the amount of Bipolar and Müller cells showed no difference(P>0.05)between all groups and when compared with those of Group I. Our study provides solid evidences that taurine possesses an antidiabetic activity, reduced loss of body weight, and less electrophysiological changes of the diabetic retina.


Parasitology ◽  
1934 ◽  
Vol 26 (2) ◽  
pp. 176-248 ◽  
Author(s):  
G. S. Graham-Smith

A detailed description of the musculature in the different regions of the alimentary canal of Calliphora erythrocephala is given, and an account of the structure and function of the crop, proventriculus, ducts of the Malpighian tubes, rectal valve and rectal papillae. It has been shown by dissections and experiments that a system of channels exists in the rectal papillae through which the body fluid probably circulates, and it is suggested that the very large cells may have functions resembling those of liver cells.


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